[media] dibusb: fix possible memory leak in dibusb_rc_query()

'buf' is malloced in dibusb_rc_query() and should be freed before
leaving from the error handling cases, otherwise it will cause
memory leak.

Fixes: ff1c123545 ("[media] dibusb: handle error code on RC query")

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/usb/dvb-usb/dibusb-common.c

@@ -382,9 +382,9 @@ int dibusb_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
 	if (buf[0] != 0)
 		deb_info("key: %*ph\n", 5, buf);
 
+ret:
 	kfree(buf);
 
-ret:
 	return ret;
 }
 EXPORT_SYMBOL(dibusb_rc_query);