For a given image, only 1 of "line stride", "(interleaved/block-compressed) row stride", or "AFBC row stride" makes sense. Yet we have all 3 fields separately, breeding confusion. This MR unifies the three into a single row stride field which generally means "the number of bytes between rows".
Unfortunately, this isn't completely trivial, because we accidentally made some broken stride definitions UABI... Whoops! To cope, add a pair of helpers to translate between legacy (UABI) strides and row strides. This should make the intent clear.
Cc @bbrezillon for the panvk changes.