If masakari receives instance failure notification it fails to
recover that instance if it is in 'paused' or 'rescued' state.
As a recovery action masakari-engine gives call to nova to stop
the instance but as nova doesn't allow this it returns 409 which
result into instance recovery failure and masakari marks that
notification status as "error".
This can be solved by maintaning consistency between the vm_state
before and after recovery but it requires to start the instance
again to gain the qemu process of an instance back alive which
might change the internal state of the instance which results into
inconsistency between instance state before and after recovery.
So as a solution this patch proposes to ignore the instance recovery
and logs a warning if the instance is in 'paused' or 'rescued' state.
Closes-Bug: #1663513
Change-Id: Id1cce45aad253527bedb58ab32f3d89637e02582
7aef2966f5