netconf: Sort bond's slave when objectivizing

To make iproute2 configurator pass testBondHwAddress, we need keep
the bond's slaves sorted. Otherwise bond's hwaddr will vary with the
order of enslaving. This work is done by initscript for ifcfg
configurator. The patch restores the nicSort function to get the
same order of initscript does.

Change-Id: I5db20ca598414ff29a368d99156b04b7f61961ae
Signed-off-by: Mark Wu <wudxw@linux.vnet.ibm.com>
Reviewed-on: http://gerrit.ovirt.org/19591
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>