Merge branch 'ronalds_buggy_gt8bit_sws'

Merge branch 'ronalds_buggy_gt8bit_sws'

* ronalds_buggy_gt8bit_sws:
  swscale: fix another yuv range conversion overflow in 16bit scaling. (cherry picked from commit 81cc7d0bd1eab0aa782ff8dd49e087025a42cdee)
  swscale: fix yuv range correction when using 16-bit scaling. (cherry picked from commit e0b8fff6c7a293e35079ba1931bd19372686b3f6)
  swscale: implement >8bit scaling support.

Conflicts:
	libswscale/swscale.c
	libswscale/utils.c
	libswscale/x86/swscale_template.c
	tests/ref/lavfi/pixdesc
	tests/ref/lavfi/pixfmts_copy
	tests/ref/lavfi/pixfmts_null
	tests/ref/lavfi/pixfmts_scale
	tests/ref/lavfi/pixfmts_vflip

Merged-by: Michael Niedermayer <michaelni@gmx.at>