CA-121347: Fix inconsistency in HA checks

1. It's currently possible to make a halted VM, with ha_restart_priority="restart", non-agile.
2. It's not possible to set ha_restart_priority="restart" on a non-agile, halted VM.
3. It's not possible to start a non-agile VM that has ha_restart_priority="restart"
4. It's not possible to make a running VM, with ha_restart_priority="restart", non-agile.
5. It's not possible to set ha_restart_priority="restart" on a non-agile, running VM.

Point #1 is inconsistent with point #2 - #2 should be allowed.

Signed-off-by: Phus Lu <phus.lu@citrix.com>
Merge pull request #1788 from phusl/CA-121347

CA-121347: Fix inconsistency in HA checks