i40e: convert i40e_phy_type_to_ethtool to new API

We are still largely using the old ethtool API macros.  This is
problematic because eventually they will be removed and they only
support 32 bits of PHY types.

This overhauls i40e_phy_type_to_ethtool to use only the new API.  Doing
this also allows us to provide much better support for newer 25G and 10G
PHY types which is included here as well.

The remaining usages of the old ethtool API will be addressed in other
patches in the series.

Signed-off-by: Alan Brady <alan.brady@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>