V4L/DVB (8757): v4l-dvb: fix a bunch of sparse warnings

Fixed a lot of sparse warnings: mostly warnings about shadowed variables
and signed/unsigned mismatches.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/usbvideo/ibmcam.c b/drivers/media/video/usbvideo/ibmcam.c
index 59166b7..cc27efe 100644
--- a/drivers/media/video/usbvideo/ibmcam.c
+++ b/drivers/media/video/usbvideo/ibmcam.c
@@ -736,12 +736,12 @@
 		 * make black color and quit the horizontal scanning loop.
 		 */
 		if (((frame->curline + 2) >= scanHeight) || (i >= scanLength)) {
-			const int j = i * V4L_BYTES_PER_PIXEL;
+			const int offset = i * V4L_BYTES_PER_PIXEL;
 #if USES_IBMCAM_PUTPIXEL
 			/* Refresh 'f' because we don't use it much with PUTPIXEL */
-			f = frame->data + (v4l_linesize * frame->curline) + j;
+			f = frame->data + (v4l_linesize * frame->curline) + offset;
 #endif
-			memset(f, 0, v4l_linesize - j);
+			memset(f, 0, v4l_linesize - offset);
 			break;
 		}