Bluetooth: Add __init and __exit marks to UART drivers

Those marks are useful to save space in the binary and in the memory.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/hci_ath.c b/drivers/bluetooth/hci_ath.c
index 5ab258b..b941dd5 100644
--- a/drivers/bluetooth/hci_ath.c
+++ b/drivers/bluetooth/hci_ath.c
@@ -217,7 +217,7 @@
 	.flush = ath_flush,
 };
 
-int ath_init(void)
+int __init ath_init(void)
 {
 	int err = hci_uart_register_proto(&athp);
 
@@ -229,7 +229,7 @@
 	return err;
 }
 
-int ath_deinit(void)
+int __exit ath_deinit(void)
 {
 	return hci_uart_unregister_proto(&athp);
 }