ice: drop driver specific structure from fwlog code

In debugfs pass ice_fwlog structure instead of ice_pf.

The debgufs dirs specific for fwlog can be stored in fwlog structure.

Add debugfs entry point to fwlog api.

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: Rinitha S <sx.rinitha@intel.com> (A Contingent worker at Intel)
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>