update devstack eswitchd to work with eswitch pbr
update devstack eswitchd to work with eswitch pbr

This patch update the devstack eswitchd to install
eswitchd as pbr installation

Change-Id: I07d8aeaa447a42de29e9972eac87993a4403b01a

openstack/networking-mlnx,stackforge/networking-mlnx,openstack/networking-mlnx,stackforge/networking-mlnx