mips: change list of files with MIPS copyright notice in mips.txt

Add files created for MP3 optimization that have MIPS copyright
 notice in them to list of files in mips.txt.
Signed-off-by: Nedeljko Babic <nbabic@mips.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

doc/mips.txt

@@ -53,8 +53,12 @@ Files that have MIPS copyright notice in them:
       amrwbdec_mips.h
       celp_filters_mips.c
       celp_math_mips.c
+      compute_antialias_fixed.h
+      compute_antialias_float.h
       lsp_mips.h
       dsputil_mips.c
       fft_mips.c
       fft_table.h
       fmtconvert_mips.c
+      mpegaudiodsp_mips_fixed.c
+      mpegaudiodsp_mips_float.c