V4L/DVB: drivers/media: Use available error codes

In each case, error codes are stored in rc, but the return value is always
0.  Return rc instead.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
local idexpression x;
constant C;
@@

if (...) { ...
  x = -C
  ... when != x
(
  return <+...x...+>;
|
  return NULL;
|
  return;
|
* return ...;
)
}
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/s2255drv.c b/drivers/media/video/s2255drv.c
index 8ec7c9a..8f74341 100644
--- a/drivers/media/video/s2255drv.c
+++ b/drivers/media/video/s2255drv.c
@@ -600,7 +600,7 @@
 	dprintk(2, "%s: [buf/i] [%p/%d]\n", __func__, buf, buf->vb.i);
 unlock:
 	spin_unlock_irqrestore(&dev->slock, flags);
-	return 0;
+	return rc;
 }
 
 static const struct s2255_fmt *format_by_fourcc(int fourcc)