r8169: mark device as not present when in PCI D3

Mark the netdevice as detached whenever we go into PCI D3hot.
This allows to remove some checks e.g. from ethtool ops because
dev_ethtool() checks for netif_device_present() in the beginning.

In this context move waking up the queue out of rtl_reset_work()
because in cases where netif_device_attach() is called afterwards
the queue should be woken up by the latter function only.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>