net: OpenFirmware GPIO based MDIO bitbang driver

This patch adds an MDIO bitbang driver that uses the GPIO library and its
OF bindings to access the bus I/Os.

Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 5997d6e..eee329f 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -15,3 +15,4 @@
 obj-$(CONFIG_REALTEK_PHY)	+= realtek.o
 obj-$(CONFIG_FIXED_PHY)		+= fixed.o
 obj-$(CONFIG_MDIO_BITBANG)	+= mdio-bitbang.o
+obj-$(CONFIG_MDIO_OF_GPIO)	+= mdio-ofgpio.o