minigbm: Add more dumb drivers

Add dumb drivers for Allwinner (sun4i-drm), MediaTek, and Rockchip
platforms. The latter two are only built and used if their respective
drivers are not selected.

BUG=b:258331312
TEST=Build Chromium VDA tests with crrev.com/c/3380427 and
     GbmDeviceWrapper using /dev/dri/card* and use_v4l2_codec=true
     Run VDA tests on RK3399 or Allwinner H6 decoding VP8 using legacy
     decoder should pass tests
     `emerge-kevin minigbm` and `emerge-cherry minigbm` should not fail

Change-Id: I82fb8815d5282f6a252a4d530eb764abb7c8c496
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/4060691
Reviewed-by: Miguel Casas-Sanchez <mcasas@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Miguel Casas <mcasas@google.com>
Commit-Queue: Chen-Yu Tsai <wenst@chromium.org>
Auto-Submit: Chen-Yu Tsai <wenst@chromium.org>
2 files changed