media: s2255drv: remove redundant assignment to variable field

The variable 'field' is being assigned a value this is never read,
it is being updated in all the following if/else combinations. The
assignment is redundant and can be removed.

Addresses-Coverity: ("Unused value")

Signed-off-by: Colin Ian King <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/usb/s2255/s2255drv.c

···
 	if (fmt == NULL)
 		return -EINVAL;
 
-	field = f->fmt.pix.field;
-
 	dprintk(vc->dev, 50, "%s NTSC: %d suggested width: %d, height: %d\n",
 		__func__, is_ntsc, f->fmt.pix.width, f->fmt.pix.height);
 	if (is_ntsc) {