driver-core: constify data for class_find_device()

All in-kernel users of class_find_device() don't really need mutable
data for match callback.

In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.

The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.

Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 044b532..dc92097 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -95,7 +95,7 @@
 
 #if IS_ENABLED(CONFIG_OF_MDIO)
 /* Helper function for of_mdio_find_bus */
-static int of_mdio_bus_match(struct device *dev, void *mdio_bus_np)
+static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
 {
 	return dev->of_node == mdio_bus_np;
 }