ice: rework of dump serdes equalizer values feature

Refactor function ice_get_tx_rx_equa() to iterate over new table of
params instead of multiple calls to ice_aq_get_phy_equalization().

Subsequent commit will extend that function by add more serdes equalizer
values to dump.

Shorten the fields of struct ice_serdes_equalization_to_ethtool for
readability purposes.

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>