The attached patch adds "mtu" and "hwaddress" to the inet6 method and
"mtu", "hwaddr" and "pointopoint" to the inet4 method (just like in
the ifupdown part).
Note: "hwaddress" can't be used with the busybox ip applet (this
function isn't implemented in bb ip yet), but it can be of use with
an external "full blown" ip package.
The patch also removes "label" from the loopback configuration,
labels (subinterfaces) aren't used with loopback interfaces.
It further solves a problem in the bootp method, "ifconfig down
%interface%" should be "ifconfig %interface% down" and it's now also
possible to use ip with bootp.
The patch is fully tested with both busybox ip and "stand-alone" ip
and I didn't saw any problems.
fdd2a0f318