ice: convert clk_freq capability into time_ref

Convert the clk_freq value into the associated time_ref frequency value
for E822 devices. This simplifies determining the time reference value
for the clock.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>