drm/msm: fix potential memleak in error branch

In function msm_submitqueue_create, the queue is a local
variable, in return -EINVAL branch, queue didn`t add to ctx`s
list yet, and also didn`t kfree, this maybe bring in potential
memleak.
Signed-off-by: Bernard Zhao <bernard@vivo.com>
[trivial commit msg fixup]
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_submitqueue.c

@@ -71,8 +71,10 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
 	queue->flags = flags;
 
 	if (priv->gpu) {
-		if (prio >= priv->gpu->nr_rings)
+		if (prio >= priv->gpu->nr_rings) {
+			kfree(queue);
 			return -EINVAL;
+		}
 
 		queue->prio = prio;
 	}