Bluetooth: AMP: Get amp_mgr reference in HS hci_conn

When assigning amp_mgr in hci_conn (type AMP_LINK) get also reference.
In hci_conn_del those references would be put for both conn types
AMP_LINK and ACL_LINK associated with amp_mgr.

Signed-off-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 7bf9a10..d5136cf 100644
--- a/net/bluetooth/a2mp.c
+++ b/net/bluetooth/a2mp.c
@@ -751,11 +751,13 @@
 }
 
 /* AMP Manager functions */
-void amp_mgr_get(struct amp_mgr *mgr)
+struct amp_mgr *amp_mgr_get(struct amp_mgr *mgr)
 {
 	BT_DBG("mgr %p orig refcnt %d", mgr, atomic_read(&mgr->kref.refcount));
 
 	kref_get(&mgr->kref);
+
+	return mgr;
 }
 
 static void amp_mgr_destroy(struct kref *kref)