Bluetooth: Do not use assignments in IF conditions

Fix checkpatch warnings concerning assignments in if conditions.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index cbaa740..28d2954 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -4724,7 +4724,10 @@
 {
 	struct l2cap_conn *conn = hcon->l2cap_data;
 
-	if (!conn && !(conn = l2cap_conn_add(hcon, 0)))
+	if (!conn)
+		conn = l2cap_conn_add(hcon, 0);
+
+	if (!conn)
 		goto drop;
 
 	BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);