drivers: Introduce device lookup variants by fwnode

Add a helper to match the firmware node handle of a device and provide
wrappers for {bus/class/driver}_find_device() APIs to avoid proliferation
of duplicate custom match functions.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: linux-usb@vger.kernel.org
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Joe Perches <joe@perches.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20190723221838.12024-4-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/roles/class.c

@@ -85,11 +85,6 @@ enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
 }
 EXPORT_SYMBOL_GPL(usb_role_switch_get_role);
 
-static int switch_fwnode_match(struct device *dev, const void *fwnode)
-{
-	return dev_fwnode(dev) == fwnode;
-}
-
 static void *usb_role_switch_match(struct device_connection *con, int ep,
 				   void *data)
 {
@@ -99,8 +94,7 @@ static void *usb_role_switch_match(struct device_connection *con, int ep,
 		if (con->id && !fwnode_property_present(con->fwnode, con->id))
 			return NULL;
 
-		dev = class_find_device(role_class, NULL, con->fwnode,
-					switch_fwnode_match);
+		dev = class_find_device_by_fwnode(role_class, con->fwnode);
 	} else {
 		dev = class_find_device_by_name(role_class, con->endpoint[ep]);
 	}