drm/amd/display: Stop leaking planes

[Why]
drm_plane_cleanup does not free the plane.

[How]
Call drm_primary_helper_destroy which will also free the plane.

Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -3301,7 +3301,7 @@ void dm_drm_plane_destroy_state(struct drm_plane *plane,
 static const struct drm_plane_funcs dm_plane_funcs = {
 	.update_plane	= drm_atomic_helper_update_plane,
 	.disable_plane	= drm_atomic_helper_disable_plane,
-	.destroy	= drm_plane_cleanup,
+	.destroy	= drm_primary_helper_destroy,
 	.reset = dm_drm_plane_reset,
 	.atomic_duplicate_state = dm_drm_plane_duplicate_state,
 	.atomic_destroy_state = dm_drm_plane_destroy_state,