net: hso: constify the struct device_type usage

Since commit aed65af1cc ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the hso_type
variable to be a constant structure as well, placing it into read-only
memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/hso.c

@@ -2465,7 +2465,7 @@ static void hso_create_rfkill(struct hso_device *hso_dev,
 	}
 }
 
-static struct device_type hso_type = {
+static const struct device_type hso_type = {
 	.name	= "wwan",
 };