When unbinding/removing the driver, we will run into the following warnings:
[  259.655198] fec 
400d1000.ethernet: 
400d1000.ethernet supply phy not found, using dummy regulator
[  259.665065] fec 
400d1000.ethernet: Unbalanced pm_runtime_enable!
[  259.672770] fec 
400d1000.ethernet (unnamed net_device) (uninitialized): Invalid MAC address: 00:00:00:00:00:00
[  259.683062] fec 
400d1000.ethernet (unnamed net_device) (uninitialized): Using random MAC address: f2:3e:93:b7:29:c1
[  259.696239] libphy: fec_enet_mii_bus: probed
Avoid these warnings by balancing the runtime PM calls during fec_drv_remove().
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
        fec_enet_mii_remove(fep);
        if (fep->reg_phy)
                regulator_disable(fep->reg_phy);
+       pm_runtime_put(&pdev->dev);
+       pm_runtime_disable(&pdev->dev);
        if (of_phy_is_fixed_link(np))
                of_phy_deregister_fixed_link(np);
        of_node_put(fep->phy_node);