nfsd4: fix FREE_STATEID lockowner leak

commit 48385408 upstream.

27b11428 ("nfsd4: remove lockowner when removing lock stateid")
introduced a memory leak.
Reported-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

fs/nfsd/nfs4state.c

@@ -3393,7 +3393,7 @@ nfsd4_free_lock_stateid(struct nfs4_ol_stateid *stp)
 	 * correspondance, and we have to delete the lockowner when we
 	 * delete the lock stateid:
 	 */
-	unhash_lockowner(lo);
+	release_lockowner(lo);
 	return nfs_ok;
 }