video-format: Add support for ARGB64 LE/BE and similar variants

Adds support for ARGB/RGBA/ABGR/BGRA64 formats in LE/BE variants.

ARGB64 is a special case, as we already support it in native endianness and it's used as the intermediate format during the conversion process, so depending on the system's endianness one of the new variants is just treated as native and the other has its components' endianness swapped accordingly.