compositor-drm: Atomic test fail when do overlay plane state test
After prepare overlay plane state. Compositor will do atomic test to see if the new state can be accepted by drm driver. But at that time, primary state is not prepared. As a result it will commit a o fb_id to driver for primary plane. On some platform, eg. imx8qxp, driver will return check fail. We need avoid commit 0 fb_id plane state to driver.