mediatek: strip scanout on resolved YVU420 format

If the FLEX_YCbCr_420_888 format gets resolved into YVU420, the backend
must strip scanout to satisfy the format support.

BUG=b:201686603
TEST=gralloctest alloc_combinations

Change-Id: I9206cb4d695b9a7eb052d2bbf2ea1032d706abb1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/3198681
Tested-by: Yiwei Zhang <zzyiwei@chromium.org>
Auto-Submit: Yiwei Zhang <zzyiwei@chromium.org>
Reviewed-by: Fei Shao <fshao@chromium.org>
Commit-Queue: Yiwei Zhang <zzyiwei@chromium.org>
1 file changed