usb: make device_type const

Make this const as it is only stored in the type field of a device
structure, which is const.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/common/ulpi.c

@@ -135,7 +135,7 @@ static void ulpi_dev_release(struct device *dev)
 	kfree(to_ulpi_dev(dev));
 }
 
-static struct device_type ulpi_dev_type = {
+static const struct device_type ulpi_dev_type = {
 	.name = "ulpi_device",
 	.groups = ulpi_dev_attr_groups,
 	.release = ulpi_dev_release,