With the addition of the variable
`om_enable_rabbitmq_high_availability`, this feature in the upgrade
task should be brought back. It is also now used in the deploy task. The
`ha-all` policy is cleared only when
`om_enable_rabbitmq_high_availability` is set to `false`.
Change-Id: Ia056aa40e996b1f0fed43c0f672466c7e4a2f547
(cherry picked from commit c85b64d1589a515da2f3cf2dcc082d15df1d6edd)