e1000e: Clear ULP configuration register on ULP exit

There have been bugs caused by HW ULP configuration settings not being
properly cleared after cable connect in V-Pro capable systems.
This caused HW to get out of sync occasionally.
The fix ensures that ULP settings are cleared in HW after
LAN cable re-connect.

Signed-off-by: Raanan Avargil <raanan.avargil@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>