Remove is_zero_ether_add() check when setting the VF default LAN address.
This check assumed that the address had been delete and zeroed before
calling ice_vc_add_mac_addr(). Now the default LAN address will be set
to the last unicast MAC address added by the VF.

The default LAN address is reported by the PF via ndo_get_vf_config.
Signed-off-by: Paul Greenwalt <paul.greenwalt@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>