V4L/DVB: Fix uninitialised variable in dvb_frontend_swzigzag

Spotted by coverity/Adrian Bunk.
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

drivers/media/dvb/dvb-core/dvb_frontend.c

@@ -329,7 +329,7 @@ static int dvb_frontend_swzigzag_autotune(struct dvb_frontend *fe, int check_wra
 
 static void dvb_frontend_swzigzag(struct dvb_frontend *fe)
 {
-	fe_status_t s;
+	fe_status_t s = 0;
 	struct dvb_frontend_private *fepriv = fe->frontend_priv;
 
 	/* if we've got no parameters, just keep idling */