plane_test: support P010

This CL adds P010 to plane_test to simplify testing this format.
Needs another CL for minigbm.

BUG=b:183760490
TEST=on volteer:
  /usr/bin/plane_test -f P010
  /usr/bin/plane_test --format NV12 --size 600x400 -p --format P010 --size 200x200 -d 200,200
work as expected.

Cq-Depend: chromium:2808788
Change-Id: I40817388180476ed702c1530c9e583d4e9ee6cb2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/drm-tests/+/2808787
Tested-by: Miguel Casas <mcasas@chromium.org>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Commit-Queue: Miguel Casas <mcasas@chromium.org>
2 files changed