video: Sort video formats correctly
AV12 should be right after A420 because it is the same format with just one plane less, instead of being next to I420/NV12 which don't have an alpha channel.
RGBP should be before GBR because it's the same format except for the more canonical component order.
See gstreamer-rs!790 (merged) which actually checks on the CI if the algorithm defined in video-format.h is implemented correctly.
CC @MarijnS95