This reverts commit a10195bb.

This commit needs some more thought, and is currently crashing kms_flip
tests. Until we figure out what's going wrong it's better to revert, and
also next time apply it to drm-misc-fixes.

Testcase: kms_flip
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104566
References: https://patchwork.freedesktop.org/series/36185/
References: https://patchwork.freedesktop.org/series/36250/Reported-by: NMarta Löfstedt <marta.lofstedt@intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>