Update source to SDL2 2.0.12

Edward Rudd

2020-05-02 03f8528315fa46c95991a34f3325d7b33ae5538c

 source/src/video/yuv2rgb/yuv_rgb.c

@@ -2,6 +2,8 @@
// Distributed under BSD 3-Clause License
#include "../../SDL_internal.h"

#if SDL_HAVE_YUV

#include "yuv_rgb.h"

#include "SDL_cpuinfo.h"
@@ -685,3 +687,4 @@

#endif //__SSE2__

#endif /* SDL_HAVE_YUV */