drm/hlcd: Use lockless gem BO free callback

No dev->struct_mutex anywhere to be seen.

Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1464630800-30786-26-git-send-email-daniel.vetter@ffwll.ch

drivers/gpu/drm/arm/hdlcd_drv.c

@@ -316,7 +316,7 @@ static struct drm_driver hdlcd_driver = {
 	.get_vblank_counter = drm_vblank_no_hw_counter,
 	.enable_vblank = hdlcd_enable_vblank,
 	.disable_vblank = hdlcd_disable_vblank,
-	.gem_free_object = drm_gem_cma_free_object,
+	.gem_free_object_unlocked = drm_gem_cma_free_object,
 	.gem_vm_ops = &drm_gem_cma_vm_ops,
 	.dumb_create = drm_gem_cma_dumb_create,
 	.dumb_map_offset = drm_gem_cma_dumb_map_offset,