[media] tua9001: fix a warning

drivers/media/tuners/tua9001.c:211:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]

Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/tuners/tua9001.c b/drivers/media/tuners/tua9001.c
index 3896684..83a6240 100644
--- a/drivers/media/tuners/tua9001.c
+++ b/drivers/media/tuners/tua9001.c
@@ -136,7 +136,7 @@
 {
 	struct tua9001_priv *priv = fe->tuner_priv;
 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
-	int ret, i;
+	int ret = 0, i;
 	u16 val;
 	u32 frequency;
 	struct reg_val data[2];