Remove the openvswitch special case upgrade code

Remove the openvswitch special case upgrade code

Removed from the tripleo_upgrade_node.sh (major upgrade) & yum_update.sh
(minor update). The workaround is no longer needed and in fact has the
opposite effect killing connectitivity to the node. The 'normal' yum
update on nodes delivers the latest openvswitch 2.6.1 with no drama.

Also adds a 'complete' message, some extra debug echo for logs
and removes the python-zaqarclient install no longer needed

Closes-Bug: 1669714
Change-Id: Icd1517bcade36781fa0da21d045ffd9ec68efc38
(cherry picked from commit 9025a3bc23834e31efc5021acaef80b8d0f5de73)