If wol state of phy hardware is enabled after reset, phy_ethtool_get_wol()
returns that wol.wolopts is true.

However, since net_device.wol_enabled is zero and this doesn't apply wol
state until calling ethtool_set_wol(), so mdio_bus_phy_may_suspend()
returns true, that is, it's in a state where phy can suspend even though
wol state is enabled.

In this inconsistency, phy_suspend() returns -EBUSY, and at last,
suspend sequence fails with the following message:

    dpm_run_callback(): mdio_bus_phy_suspend+0x0/0x58 returns -16
    PM: Device 65000000.ethernet-ffffffff:01 failed to suspend: error -16
    PM: Some devices failed to suspend, or early wake event detected

In order to fix the above issue, this patch forces to set initial wol state
to disabled as default.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>