dlm: mask sk_shutdown value

The sk->sk_shutdown value is flag value so use masking to check if
RCV_SHUTDOWN is set as other possible values like SEND_SHUTDOWN can set
as well.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Tested-by: Heming zhao <heming.zhao@suse.com>
Reviewed-by: Heming zhao <heming.zhao@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>

Author: Alexander Aring

fs/dlm/lowcomms.c

@@ -533,7 +533,7 @@ static void lowcomms_state_change(struct sock *sk)
 	/* SCTP layer is not calling sk_data_ready when the connection
 	 * is done, so we catch the signal through here.
 	 */
-	if (sk->sk_shutdown == RCV_SHUTDOWN)
+	if (sk->sk_shutdown & RCV_SHUTDOWN)
 		lowcomms_data_ready(sk);
 }