[FFmpeg-devel] Add LSX optimization in avcodec and swscale.

[Hao Chen]

v1: Add LSX optimization in avcodec and swscale, due to the 2K series CPUs only support lsx.
v2: Modified the implementation of some functions and added support for the checkasm --bench feature.

[PATCH v2 1/7] avcodec/la: add LSX optimization for h264 idct.
[PATCH v2 2/7] avcodec/la: Add LSX optimization for loop filter.
[PATCH v2 3/7] avcodec/la: Add LSX optimization for h264 chroma and
[PATCH v2 4/7] avcodec/la: Add LSX optimization for h264 qpel.
[PATCH v2 5/7] swscale/la: Optimize the functions of the swscale.
[PATCH v2 6/7] swscale/la: Add following builtin optimized functions.
[PATCH v2 7/7] avutil/la: Add function performance testing.