drm/malidp: Annotate dma-fence critical section in commit path

Again needs to be put right after the call to
drm_atomic_helper_commit_hw_done(), since that's the last thing which
can hold up a subsequent atomic commit.

No surprises here.

Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: "James (Qian) Wang" <james.qian.wang@arm.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Mihail Atanassov <mihail.atanassov@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210121152959.1725404-6-daniel.vetter@ffwll.ch