gfs2: fix possible reference leak in gfs2_check_blk_type

In the fail path of gfs2_check_blk_type, forgetting to call
gfs2_glock_dq_uninit will result in rgd_gh reference leak.
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/rgrp.c

@@ -2529,13 +2529,13 @@ int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
 
 	rbm.rgd = rgd;
 	error = gfs2_rbm_from_block(&rbm, no_addr);
-	if (WARN_ON_ONCE(error))
-		goto fail;
-
-	if (gfs2_testbit(&rbm, false) != type)
-		error = -ESTALE;
+	if (!WARN_ON_ONCE(error)) {
+		if (gfs2_testbit(&rbm, false) != type)
+			error = -ESTALE;
+	}
 
 	gfs2_glock_dq_uninit(&rgd_gh);
+
 fail:
 	return error;
 }