drm/msm/dpu: clean up dpu_rm_check_property_topctl declaration

Definition was removed already. Clean up header declaration.

changes in v2:
	- none

Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>