V4L/DVB: drivers/media/video/uvc: Use kmemdup

Use kmemdup when some other buffer is immediately copied into the
allocated region.

A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
statement S;
@@

-  to = \(kmalloc\|kzalloc\)(size,flag);
+  to = kmemdup(from,size,flag);
   if (to==NULL || ...) S
-  memcpy(to, from, size);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/uvc/uvc_driver.c

@@ -637,14 +637,13 @@ static int uvc_parse_streaming(struct uvc_device *dev,
 	}
 	streaming->header.bControlSize = n;
 
-	streaming->header.bmaControls = kmalloc(p*n, GFP_KERNEL);
+	streaming->header.bmaControls = kmemdup(&buffer[size], p * n,
+						GFP_KERNEL);
 	if (streaming->header.bmaControls == NULL) {
 		ret = -ENOMEM;
 		goto error;
 	}
 
-	memcpy(streaming->header.bmaControls, &buffer[size], p*n);
-
 	buflen -= buffer[0];
 	buffer += buffer[0];