ice: Enable 1PPS out from CGU for E825C products

Implement configuring 1PPS signal output from CGU. Use maximal amplitude
because Linux PTP pin API does not have any way for user to set signal
level.

This change is necessary for E825C products to properly output any
signal from 1PPS pin.

Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Sergey Temerkhanov <sergey.temerkhanov@intel.com>
Co-developed-by: Karol Kolacinski <karol.kolacinski@intel.com>
Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>