net: Add IPQ40xx MDIO driver

This adds the driver for the IPQ40xx built-in MDIO.
This will be needed to support future PHY driver.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
diff --git a/MAINTAINERS b/MAINTAINERS
index d5a418d..a80045f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -242,6 +242,7 @@
 F:	drivers/reset/reset-ipq4019.c
 F:	drivers/phy/phy-qcom-ipq4019-usb.c
 F:	drivers/spi/spi-qup.c
+F:	drivers/net/mdio-ipq4019.c
 
 ARM MARVELL KIRKWOOD ARMADA-XP ARMADA-38X ARMADA-37XX ARMADA-7K/8K
 M:	Stefan Roese <sr@denx.de>