Bluetooth: Add unlocked __l2cap_chan_add function

Add unlocked L2CAP channel add function. Unlocked version will
be used in later patches.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Reviewed-by: Ulisses Furquim <ulisses@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

net/bluetooth/l2cap_core.c

@@ -300,7 +300,7 @@ void l2cap_chan_destroy(struct l2cap_chan *chan)
 	l2cap_chan_put(chan);
 }
 
-static void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
+void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 {
 	BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
 			chan->psm, chan->dcid);
@@ -346,8 +346,13 @@ static void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 
 	l2cap_chan_hold(chan);
 
-	mutex_lock(&conn->chan_lock);
 	list_add(&chan->list, &conn->chan_l);
+}
+
+void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
+{
+	mutex_lock(&conn->chan_lock);
+	__l2cap_chan_add(conn, chan);
 	mutex_unlock(&conn->chan_lock);
 }