Bluetooth: Keep MGMT pending queue ordered FIFO

Small change to add new commands to tail of the list, and find/remove them
from the head of the list.

Signed-off-by: Brian Gix <brian.gix@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/mgmt_util.c

@@ -297,7 +297,7 @@ struct mgmt_pending_cmd *mgmt_pending_add(struct sock *sk, u16 opcode,
 	if (!cmd)
 		return NULL;
 
-	list_add(&cmd->list, &hdev->mgmt_pending);
+	list_add_tail(&cmd->list, &hdev->mgmt_pending);
 
 	return cmd;
 }