[RHV] General command validation failure message when enabling Power Management

Issue

Enabling Power Management on the HE host fails with General command validation failure message.
It is also possible to see in the engine.log following error

2021-06-29 13:47:03,677Z ERROR [org.ovirt.engine.core.bll.hostdeploy.UpdateVdsCommand] (default task-335) [8af2ab3c-d201-46f7-85ba-6acc4d7426fa] Error during ValidateFailure.: java.lang.NullPointerException
        at deployment.engine.ear.bll.jar//org.ovirt.engine.core.bll.hostedengine.HostedEngineHelper.getStoragePoolId(HostedEngineHelper.java:103)
        at deployment.engine.ear.bll.jar//org.ovirt.engine.core.bll.validator.HostValidator.supportsDeployingHostedEngine(HostValidator.java:178)
        at deployment.engine.ear.bll.jar//org.ovirt.engine.core.bll.hostdeploy.UpdateVdsCommand.validate(UpdateVdsCommand.java:155)
        at deployment.engine.ear.bll.jar//org.ovirt.engine.core.bll.CommandBase.internalValidateInTransaction(CommandBase.java:824)