USB: HWA: constify hc_driver structures

The hc_driver structure is only passed as the first argument to
usb_create_hcd, which is declared as const.  Thus the hc_driver structure
itself can be const.

Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/hwa-hc.c

@@ -614,7 +614,7 @@ static int wa_fill_descr(struct wahc *wa)
 	return result;
 }
 
-static struct hc_driver hwahc_hc_driver = {
+static const struct hc_driver hwahc_hc_driver = {
 	.description = "hwa-hcd",
 	.product_desc = "Wireless USB HWA host controller",
 	.hcd_priv_size = sizeof(struct hwahc) - sizeof(struct usb_hcd),