ice: move LAG function in code to prepare for Active-Active

In the SRIOV LAG Active-Active, the functions ice_lag_cfg_pf_fltr's
and ice_lag_config_eswitch's content are moved to earlier locations
in the source file.  Also, ice_lag_cfg_pf_fltr is renamed, and its
flow is changed.

To reduce the delta in the larger patch, move the original functions
to their new location so that only functional changes are needed in
the larger patch.

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>