Reinstantiate parts of code that were accidentally removed

Reinstantiate parts of code that were accidentally removed

With commit fb25385d34e604d2f670cebe3e03fd57c14fa6be
"Rework the pacemaker_common_functions for M..N upgrades" we
accidentally removed some lines that fixed M/N upgrade issues.
Namely:
extraconfig/tasks/major_upgrade_controller_pacemaker_1.sh

  -# https://bugzilla.redhat.com/show_bug.cgi?id=1284047
  -# Change-Id: Ib3f6c12ff5471e1f017f28b16b1e6496a4a4b435
  -crudini --set /etc/ceilometer/ceilometer.conf DEFAULT rpc_backend rabbit
  -# https://bugzilla.redhat.com/show_bug.cgi?id=1284058
  -# Ifd1861e3df46fad0e44ff9b5cbd58711bbc87c97 Swift Ceilometer middleware no longer exists
  -crudini --set /etc/swift/proxy-server.conf pipeline:main pipeline "catch_errors healthcheck cache ratelimit tempurl formpost authtoken keystone staticweb proxy-logging proxy-server"
  -# LP: 1615035, required only for M/N upgrade.
  -crudini --set /etc/nova/nova.conf DEFAULT scheduler_host_manager host_manager

extraconfig/tasks/major_upgrade_controller_pacemaker_2.sh
  nova-manage db sync
- nova-manage api_db sync

This patch simply puts that code back without reverting the
whole commit that broke things, because that is needed.

Closes-Bug: #1627448

Change-Id: I89124ead8928ff33e6b6907a7c2178169e91f4e6