Modify NV12 allowed buffer usages for camera capture use case

We use SCANOUT_VEA_READ_CAMERA_AND_CPU_READ_WRITE for camera
capture use scenario in Chrome. Therefore, NV12 format must be
allowed for all those usage masks. This CL modifies the usages on
all platforms.

BUG=chromium:982201
TEST=video.EncodeAccel.vp8_720p_i420 on eve

Change-Id: I7880e64049f3bbf9dd1c177619e41362baf641f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/2240995
Reviewed-by: Tomasz Figa <[email protected]>
Reviewed-by: Gurchetan Singh <[email protected]>
Tested-by: Hirokazu Honda <[email protected]>
Commit-Queue: Hirokazu Honda <[email protected]>
5 files changed