x86/synth_filter: compile avx and fma3 functions unconditionally

Fixes compilation failures with "--disable-{avx,fma3} --disable-optimizations"
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/x86/dcadsp.asm

@@ -416,11 +416,7 @@ SYNTH_FILTER
 %endif
 INIT_XMM sse2
 SYNTH_FILTER
-%if HAVE_AVX_EXTERNAL
 INIT_YMM avx
 SYNTH_FILTER
-%endif
-%if HAVE_FMA3_EXTERNAL
 INIT_YMM fma3
 SYNTH_FILTER
-%endif

libavcodec/x86/dcadsp_init.c

@@ -82,13 +82,7 @@ SYNTH_FILTER_FUNC(sse)
 #endif
 SYNTH_FILTER_FUNC(sse2)
 SYNTH_FILTER_FUNC(avx)
-static void synth_filter_fma3(FFTContext *imdct,
-                             float *synth_buf_ptr, int *synth_buf_offset,
-                             float synth_buf2[32], const float window[512],
-                             float out[32], const float in[32], float scale);
-#if HAVE_FMA3_EXTERNAL
 SYNTH_FILTER_FUNC(fma3)
-#endif
 #endif /* HAVE_YASM */
 
 av_cold void ff_synth_filter_init_x86(SynthFilterContext *s)