entering the KMS mode.
Before we configure connector/encoder/crtc, the function of
drm_helper_disable_unused_function can disable all the possible outputs/crtcs.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Rafal Milecki <zajec5@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
·Õ°k”