[media] saa7146: fix compile warning

Fall-out from the recent struct v4l2_framebuffer change.

drivers/media/common/saa7146/saa7146_fops.c: In function ‘saa7146_vv_init’:
drivers/media/common/saa7146/saa7146_fops.c:536:6: warning: assignment from incompatible pointer type [enabled by default]
  fmt = &vv->ov_fb.fmt;
        ^
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/common/saa7146/saa7146_fops.c

@@ -533,13 +533,12 @@ int saa7146_vv_init(struct saa7146_dev* dev, struct saa7146_ext_vv *ext_vv)
 	if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
 		saa7146_vbi_uops.init(dev,vv);
 
-	fmt = &vv->ov_fb.fmt;
-	fmt->width = vv->standard->h_max_out;
-	fmt->height = vv->standard->v_max_out;
-	fmt->pixelformat = V4L2_PIX_FMT_RGB565;
-	fmt->bytesperline = 2 * fmt->width;
-	fmt->sizeimage = fmt->bytesperline * fmt->height;
-	fmt->colorspace = V4L2_COLORSPACE_SRGB;
+	vv->ov_fb.fmt.width = vv->standard->h_max_out;
+	vv->ov_fb.fmt.height = vv->standard->v_max_out;
+	vv->ov_fb.fmt.pixelformat = V4L2_PIX_FMT_RGB565;
+	vv->ov_fb.fmt.bytesperline = 2 * vv->ov_fb.fmt.width;
+	vv->ov_fb.fmt.sizeimage = vv->ov_fb.fmt.bytesperline * vv->ov_fb.fmt.height;
+	vv->ov_fb.fmt.colorspace = V4L2_COLORSPACE_SRGB;
 
 	fmt = &vv->video_fmt;
 	fmt->width = 384;