e1000e: NVM write protect access removed from SPT HW

The call to e1000e_write_protect_nvm_ich8lan() is no longer supported by HW.
Access to these registers causes a system freeze in A step hardware and is
ignored in B step hardware. This function must not be called in hardware
newer than LPT.

Signed-off-by: Yanir Lubetkin <yanirx.lubetkin@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>