[media] si4713: fix error return code

Return a negative error code on failure.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret; expression e1,e2;
@@
(
if (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/radio/si4713/si4713.c

@@ -1609,8 +1609,10 @@ static int si4713_probe(struct i2c_client *client,
 		return 0;
 
 	si4713_pdev = platform_device_alloc("radio-si4713", -1);
-	if (!si4713_pdev)
+	if (!si4713_pdev) {
+		rval = -ENOMEM;
 		goto put_main_pdev;
+	}
 
 	si4713_pdev_pdata.subdev = client;
 	rval = platform_device_add_data(si4713_pdev, &si4713_pdev_pdata,