libx265: Use 16-bit SAR

The spec says it is 16 bits.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
libx265: Only set the SAR if it is valid

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
avcodec/imgconvert: fix nb_components and depth for PAL8 in get_pix_fmt_score()

This causes us to favor RGB8 over PAL8 when FF_LOSS_COLORQUANT is used

It probably makes sense to reinvestigate the exact scoring of pal8 when
our pal8 support improves to be supperior to rgb8

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