tulip: dmfe: use generic power management

With legacy PM hooks, it was the responsibility of a driver to manage PCI
states and also the device's power state. The generic approach is to let the
PCI core handle the work.

The legacy suspend() and resume() were making use of
pci_read/write_config_dword() to enable/disable wol. Driver editing
configuration registers of a device is not recommended. Thus replace them
all with device_wakeup_enable/disable().

Compile-tested only.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>