staging: fieldbus: make anybus_bus const

Now that the driver core can properly handle constant struct bus_type,
move the anybus_bus variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20240203-bus_cleanup-staging-v1-1-a13448ddb4c7@marliere.netSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fieldbus/anybuss/host.c

@@ -1195,7 +1195,7 @@ static void anybus_bus_remove(struct device *dev)
 		adrv->remove(to_anybuss_client(dev));
 }
 
-static struct bus_type anybus_bus = {
+static const struct bus_type anybus_bus = {
 	.name		= "anybuss",
 	.match		= anybus_bus_match,
 	.probe		= anybus_bus_probe,