i40e: fix missing DA cable check

When a Direct Attach (DA) cable is used, if the i40e_set_settings
function is called it would return an error. Add the DA type so
the function won't fail.

Change-ID: I2b802f27a5d91cfefa72fd1f852acb4d74647a8e
Signed-off-by: Serey Kong <serey.kong@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>