deployUtil: Remove null character from the id on IBM POWER

The hardware id for IBM POWER machines had a trailing null character that
caused errors in the oVirt engine. (This patch was also submitted to the
oVirt host deploy project).

Change-Id: I05d29598e025ae94d13036c8fca6b054343f54fe
Signed-off-by: Vitor de Lima <vitor.lima@eldorado.org.br>
Reviewed-on: http://gerrit.ovirt.org/17423
Reviewed-by: Alon Bar-Lev <alonbl@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>