There was never a property for it anyway, so it never got serialized
across D-Bus, because it was folded into the "password" property in
wpa_supplicant between 0.5 and 0.6.
This commit implements MAC cloning feature in NetworkManager. To support that,
'PermHwAddress' property is added into *.Device.Wired and *.Device.Wireless
interfaces. The permanent MAC address is obtained when creating the device, and
is used for 'locking' connections to the device. If a cloned MAC is specified
in connection to be activated, the MAC is set to the interface in stage1. While
disconecting, the permanent MAC is set back to the interface.
nmcli uses its own code to dump connections' details instead of
libnm-util's nm_connection_dump(). It allows to structure output
and present values of the settings according to nmcli needs.