[media] go7007-v4l2: warning fix: index is unsigned, so it will never be below 0

drivers/staging/media/go7007/go7007-v4l2.c: In function 'vidioc_qbuf':
drivers/staging/media/go7007/go7007-v4l2.c:815:2: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/go7007/go7007-v4l2.c

@@ -812,7 +812,7 @@ static int vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *buf)
 		return retval;
 
 	mutex_lock(&gofh->lock);
-	if (buf->index < 0 || buf->index >= gofh->buf_count)
+	if (buf->index >= gofh->buf_count)
 		goto unlock_and_return;
 
 	gobuf = &gofh->bufs[buf->index];