media: imx7: fix smatch error

Fixes this smatch error:

drivers/staging/media/imx/imx7-mipi-csis.c:716 mipi_csis_set_fmt() error: we previously assumed 'fmt' could be null (see line 709)

fmt is never NULL, so remove the 'fmt &&' condition.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/staging/media/imx/imx7-mipi-csis.c

@@ -706,7 +706,7 @@ static int mipi_csis_set_fmt(struct v4l2_subdev *mipi_sd,
 	fmt = mipi_csis_get_format(state, cfg, sdformat->which, sdformat->pad);
 
 	mutex_lock(&state->lock);
-	if (fmt && sdformat->pad == CSIS_PAD_SOURCE) {
+	if (sdformat->pad == CSIS_PAD_SOURCE) {
 		sdformat->format = *fmt;
 		goto unlock;
 	}