Input: usbtouchscreen - switch to using kmemdup()

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

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 99330bb..0b0ae2e 100644
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -811,12 +811,11 @@
 
 	priv = usbtouch->priv;
 
-	priv->ack_buf = kmalloc(sizeof(nexio_ack_pkt), GFP_KERNEL);
+	priv->ack_buf = kmemdup(nexio_ack_pkt, sizeof(nexio_ack_pkt),
+				GFP_KERNEL);
 	if (!priv->ack_buf)
 		goto err_priv;
 
-	memcpy(priv->ack_buf, nexio_ack_pkt, sizeof(nexio_ack_pkt));
-
 	priv->ack = usb_alloc_urb(0, GFP_KERNEL);
 	if (!priv->ack) {
 		dbg("%s - usb_alloc_urb failed: usbtouch->ack", __func__);