NFS: Fix missing unlock in nfs_unlink()

Add the missing unlock before goto.

Fixes: 3c59366c ("NFS: don't unhash dentry during unlink/rename")
Signed-off-by: NSun Ke <sunke32@huawei.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/dir.c

@@ -2484,8 +2484,10 @@ int nfs_unlink(struct inode *dir, struct dentry *dentry)
 	 */
 	error = -ETXTBSY;
 	if (WARN_ON(dentry->d_flags & DCACHE_NFSFS_RENAMED) ||
-	    WARN_ON(dentry->d_fsdata == NFS_FSDATA_BLOCKED))
+	    WARN_ON(dentry->d_fsdata == NFS_FSDATA_BLOCKED)) {
+		spin_unlock(&dentry->d_lock);
 		goto out;
+	}
 	if (dentry->d_fsdata)
 		/* old devname */
 		kfree(dentry->d_fsdata);