WIP: video: Add MT21C support

This is just an experiement, basically this code only detiled the format as
this is all we know about it for now.

This is NV12, tiled 16x32 (linear), but then in each tiles there seems to be a
compression and in the chroma there seems to be some extra data at the bottom
right. The sample does not have anough chroma complexity to show if there is
some bit that does not get compressed.
25 jobs for mt21c-detiler in 49 seconds
Status Name Job ID Coverage
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