gralloc: move the logic to strip BO_USE_HW_VIDEO_ENCODER to the backends

BUG=b:199524294
TEST=CQ

Change-Id: I2b36a0ef17cd6ecb77723d4a9d95196ad27ff4ad
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/3200148
Commit-Queue: Yiwei Zhang <zzyiwei@chromium.org>
Tested-by: Yiwei Zhang <zzyiwei@chromium.org>
Tested-by: Jason Macnak <natsu@google.com>
Reviewed-by: Jason Macnak <natsu@google.com>
Reviewed-by: Chia-I Wu <olv@google.com>
4 files changed