Bluetooth: Add error mapping for Directed Advertising Timeout

When a timeout occurs using directed advertising a 0x3c error gets
generated. Since the operation is analogous to conventional connection
creation map this to the usual EHOSTDOWN error.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/lib.c

@@ -58,6 +58,7 @@ int bt_to_errno(__u16 code)
 		return EIO;
 
 	case 0x04:
+	case 0x3c:
 		return EHOSTDOWN;
 
 	case 0x05: