ice: increase the GNSS data polling interval to 20 ms

Double the GNSS data polling interval from 10 ms to 20 ms.
According to Karol Kolacinski from the Intel team, they have been
planning to make this change.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Sunitha Mekala <sunithax.d.mekala@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>