i40e: add support for triggering EMPR

Allow debugfs to trigger a reset called EMPR.

Change-Id: I2f6600a8242759ec60c8198d03f70c2b774e0740
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --cc drivers/net/ethernet/intel/i40e/i40e.h
Simple merge

diff --cc drivers/net/ethernet/intel/i40e/i40e_debugfs.c
Simple merge

diff --cc drivers/net/ethernet/intel/i40e/i40e_main.c
Simple merge