[media] rtl2832: fix compiler warning

>From the daily build:

rtl2832.c: In function 'rtl2832_read_status':
rtl2832.c:703:12: warning: 'tmp' may be used uninitialized in this function [-Wmaybe-uninitialized]
  } else if (tmp == 10) {
            ^

The code is OK, it's just the compiler that cannot figure out what's
going on. So just init 'tmp' to 0.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/dvb-frontends/rtl2832.c

@@ -685,7 +685,7 @@ static int rtl2832_read_status(struct dvb_frontend *fe, fe_status_t *status)
 	struct rtl2832_dev *dev = fe->demodulator_priv;
 	struct i2c_client *client = dev->client;
 	int ret;
-	u32 tmp;
+	u32 tmp = 0;
 
 	dev_dbg(&client->dev, "\n");