media: dvb-frontends/rtl2832.c: fix missing error code

Fixes this smatch warning:

drivers/media/dvb-frontends/rtl2832.c:702 rtl2832_read_status() warn: missing error code 'ret'

'ret' is indeed not set, so set it to -EINVAL so a proper error
code is returned.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/dvb-frontends/rtl2832.c

@@ -698,6 +698,7 @@ static int rtl2832_read_status(struct dvb_frontend *fe, enum fe_status *status)
 			goto err;
 
 		constellation = (u8tmp >> 2) & 0x03; /* [3:2] */
+		ret = -EINVAL;
 		if (constellation > CONSTELLATION_NUM - 1)
 			goto err;