Bluetooth: Free the l2cap channel list only when refcount is zero

Move the l2cap channel list chan->global_l under the refcnt
protection and free it based on the refcnt.

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
Signed-off-by: Syam Sidhardhan <s.syam@samsung.com>
Reviewed-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c
index 79af661..0760d1f 100644
--- a/net/bluetooth/a2mp.c
+++ b/net/bluetooth/a2mp.c
@@ -416,7 +416,7 @@
 
 static void a2mp_chan_close_cb(struct l2cap_chan *chan)
 {
-	l2cap_chan_destroy(chan);
+	l2cap_chan_put(chan);
 }
 
 static void a2mp_chan_state_change_cb(struct l2cap_chan *chan, int state)