drm-tests: add support for EGL_EXT_platform_device to null_platform_test and bsdrm.

Add two new command line options to select display device and renderer device.
Modify bsdrm to query list of devices from egl and initialize egl on requested
device.

BUG=chromium:970850
TEST=run null_platform_test -d i915 -r amdgpu -m DRM_FORMAT_MOD_LINEAR

Change-Id: I8ce5b089f396b098351aedc53353f24f856c6dac
Signed-off-by: Dominik Behr <dbehr@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/drm-tests/+/1641631
Reviewed-by: Zach Reizner <zachr@chromium.org>
5 files changed