Regression from 4563a86f.
Both need stdint.h included before the respective x264.h and xavs.h.

Old require() used different, separate checks that didn't actually
need stdint.h to work. require2()'s (now require) check_func_headers()
does include stdint.h but only after the custom headers.

For libxavs this would also be consequently fixed by libav's
commit 20abcaa2 which wasn't merged yet.

vp9_diag_downleft_16x16_10bpp_c: 263.0
vp9_diag_downleft_16x16_10bpp_sse2: 44.7
vp9_diag_downleft_16x16_10bpp_ssse3: 32.5
vp9_diag_downleft_16x16_10bpp_avx: 31.9
vp9_diag_downleft_16x16_10bpp_avx2: 25.7
vp9_diag_downleft_16x16_12bpp_c: 264.7
vp9_diag_downleft_16x16_12bpp_sse2: 44.4
vp9_diag_downleft_16x16_12bpp_ssse3: 32.0
vp9_diag_downleft_16x16_12bpp_avx: 32.4
vp9_diag_downleft_16x16_12bpp_avx2: 25.5

Benchmarked with 10000 runs
Signed-off-by: Ilia <zakne0ne@gmail.com>
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

checkasm --bench results with 5000 runs

pred16x16_tm_vp8_c: 302.8
pred16x16_tm_vp8_mmx: 101.4
pred16x16_tm_vp8_mmxext: 95.5
pred16x16_tm_vp8_sse2: 95.1
pred16x16_tm_vp8_avx2: 38.2
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

* commit 'ab3554e1':
  configure: Drop check_lib()/require() in favor of check_lib2()/require2()
Merged-by: Clément Bœsch <u@pkh.me>

* commit '468bfe38':
  ppc: mpegvideo: Add proper runtime AltiVec detection
Merged-by: Clément Bœsch <u@pkh.me>

* commit '6ce93757':
  ppc: Update #endif comments

This commit is mostly a noop as we seem to support PPC LE (see
902ce2a6). Only the h264 chunks are
updated.
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'caccb3a0':
  audiodsp: ppc: Add VSX variant
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'e89cef40':
  checkasm: Read the unsigned value as it should
Merged-by: Clément Bœsch <u@pkh.me>

* commit '75d642a9':
  vaapi_vp8: Explicitly include libva vp8 decode header
  vaapi_decode: Ignore the profile when not useful
  lavc/vaapi: Add VP8 decode hwaccel
  vp8: Add hwaccel hooks

This merge is a noop as these commits are already under review on the
mailing list. doc/libav-merge.txt is updated to track its progress.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '131a85a1':
  utvideo: Change type of array stride parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '52730e0f':
  iir_filter: Change type of array stride parameters to ptrdiff_t

The merge also updates the MIPS code and drop the extra log.h include.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '6b527629':
  error_resilience: Change type of array stride parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'ec903058':
  configure: Simplify clock_gettime() test

nanosleep check also updated.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '3aa9d37d':
  build: Fix directory dependencies of tests/pixfmts.mak target

This might not be necessary given our mkdirs in the configure, but it
probably doesn't hurt.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '0e5dde73':
  configure: Fix --disable-pod2man / --disable-texi2html

This commit is a noop, we have dedicated documentation option for this
purpose.
Merged-by: Clément Bœsch <u@pkh.me>

The configure has the --disable-manpages option for this purpose, and
--disable-pod2man is currently ignored due to that. This is also
consistent with the other documentation options.

* commit 'b8c2d407':
  configure: Simplify libopenjpeg check

This commit is a noop, our libopenjpeg check is already "simpler".
Merged-by: Clément Bœsch <u@pkh.me>

* commit '2610c952':
  configure: Move initial VAAPI check to a more sensible place

This commit is a noop, see 17989dcfMerged-by: Clément Bœsch <u@pkh.me>

* commit '5b5ed92d':
  sanm: Change type of array pitch parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '73f5e17a':
  copy_block: Change type of array stride parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '21e500ba':
  svq1dec: Change type of array pitch parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '746c56b7':
  indeo: Change type of array pitch parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '4fb311c8':
  Drop memalign hack

Merged, as this may indeed be uneeded since
46e3936f.
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'f01f7a78':
  hwcontext_dxva2: use the special UC copy for downloading frames
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'd7bc52bf':
  imgutils: add a function for copying image data from GPU mapped memory
Merged-by: Clément Bœsch <u@pkh.me>

* commit '24da4303':
  Changelog: mark the release 12 branch

This commit is a noop.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '851960f6':
  lavc: Remove old vaapi decode infrastructure
  avconv_vaapi: Convert to use hw_frames_ctx only
  vaapi_mpeg4: Convert to use the new VAAPI hwaccel code
  vaapi_vc1: Convert to use the new VAAPI hwaccel code
  vaapi_mpeg2: Convert to use the new VAAPI hwaccel code
  vaapi_h264: Convert to use the new VAAPI hwaccel code
  lavc: Rewrite VAAPI decode infrastructure

This merge is a noop, these commits have already been cherry-picked.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '72eba655':
  wmavoice: Simplify GetBitContext initialization

This commit is a noop. We don't have that code anymore since
3deb4b54.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '80fc75d5':
  Changelog: Mention mov with multiple stsd
Merged-by: Clément Bœsch <u@pkh.me>

* commit '728e80cd':
  High Definition Compatible Digital (HDCD) decoder filter, using libhdcd

This commit is a noop, we have that code natively.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '95f80293':
  avprobe: Fix memory leak

This commit is a noop, ffprobe is not affected.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '8db804e8':
  mov: Remove old b-frame/video delay heuristic

This commit is a noop, see 425be3c8Merged-by: Clément Bœsch <u@pkh.me>

* commit 'eb96505b':
  mov: Remove ancient heuristic hack

This commit is a noop, see 04f8d312Merged-by: Clément Bœsch <u@pkh.me>

Reduce diff with Libav.