staging: vboxvideo: switch to drm_*{get,put} helpers

drm_*_reference() and drm_*_unreference() functions are just
compatibility alias for drm_*_get() and drm_*_put() adn should not be
used by new code. So convert all users of compatibility functions to use
the new APIs.

Signed-off-by: Cihangir Akturk <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/vboxvideo/vbox_fb.c

···
 				vbox_bo_unpin(bo);
 			vbox_bo_unreserve(bo);
 		}
-		drm_gem_object_unreference_unlocked(afb->obj);
+		drm_gem_object_put_unlocked(afb->obj);
 		afb->obj = NULL;
 	}
 	drm_fb_helper_fini(&fbdev->helper);

drivers/staging/vboxvideo/vbox_main.c

···
 	struct vbox_framebuffer *vbox_fb = to_vbox_framebuffer(fb);
 
 	if (vbox_fb->obj)
-		drm_gem_object_unreference_unlocked(vbox_fb->obj);
+		drm_gem_object_put_unlocked(vbox_fb->obj);
 
 	drm_framebuffer_cleanup(fb);
 	kfree(fb);
···
 err_free_vbox_fb:
 	kfree(vbox_fb);
 err_unref_obj:
-	drm_gem_object_unreference_unlocked(obj);
+	drm_gem_object_put_unlocked(obj);
 	return ERR_PTR(ret);
 }
 
···
 		return ret;
 
 	ret = drm_gem_handle_create(file, gobj, &handle);
-	drm_gem_object_unreference_unlocked(gobj);
+	drm_gem_object_put_unlocked(gobj);
 	if (ret)
 		return ret;
 
···
 	bo = gem_to_vbox_bo(obj);
 	*offset = vbox_bo_mmap_offset(bo);
 
-	drm_gem_object_unreference(obj);
+	drm_gem_object_put(obj);
 	ret = 0;
 
 out_unlock:

drivers/staging/vboxvideo/vbox_mode.c

···
 out_unreserve_bo:
 	vbox_bo_unreserve(bo);
 out_unref_obj:
-	drm_gem_object_unreference_unlocked(obj);
+	drm_gem_object_put_unlocked(obj);
 
 	return ret;
 }