Build: remove old ovirt-node packages in the ovirt local repository

Remove the old ovirt-node packages otherwise there will be more and
more temporary ovirt-node packages in the ovirt local repository.

Change-Id: Idc45b6cc6fc0307a985e84aff4695a87b7c9b894
Signed-off-by: Wenyi Gao <wenyi@linux.vnet.ibm.com>