i40e: Turn flow director off in MFP mode

The driver needs to set the MFP flag earlier in i40e_sw_init
and then can use that flag to decide if other hardware
work-arouds are required.

Change-ID: Ib17ad1e3485f57b28845ab4722294a99f203bd48
Signed-off-by: Catherine Sullivan <catherine.sullivan@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>