drm/msm/mdp5: Don't leak some plane state

Apparently no one noticed that mdp5 plane states leak like a sieve
ever since we introduced plane_state->commit refcount a few years ago
in 21a01ab ("drm/atomic: Fix freeing connector/plane state too
early by tracking commits, v3.")

Fix it by using the right helpers.

Fixes: 21a01ab ("drm/atomic: Fix freeing connector/plane state too early by tracking commits, v3.")
Cc: Maarten Lankhorst <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Rob Clark <[email protected]>
Cc: Abhinav Kumar <[email protected]>
Cc: Dmitry Baryshkov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Reported-and-tested-by: [email protected]
Cc: [email protected]
Signed-off-by: Daniel Vetter <[email protected]>
Reviewed-by: Rob Clark <[email protected]>
Reviewed-by: Dmitry Baryshkov <[email protected]>
Reviewed-by: Abhinav Kumar <[email protected]>
Patchwork: https://patchwork.freedesktop.org/patch/551236/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Dmitry Baryshkov <[email protected]>

Author: danvet

drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c

@@ -130,8 +130,7 @@ static void mdp5_plane_destroy_state(struct drm_plane *plane,
 {
 	struct mdp5_plane_state *pstate = to_mdp5_plane_state(state);
 
-	if (state->fb)
-		drm_framebuffer_put(state->fb);
+	__drm_atomic_helper_plane_destroy_state(state);
 
 	kfree(pstate);
 }