ice: Fix replacing VF hardware MAC to existing MAC filter

VF was not able to change its hardware MAC address in case
the new address was already present in the MAC filter list.
Change the handling of VF add mac request to not return
if requested MAC address is already present on the list
and check if its hardware MAC needs to be updated in this case.

Fixes: ed4c068d ("ice: Enable ip link show on the PF to display VF unicast MAC(s)")
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Tested-by: Tony Brelinski <tony.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>