Support for ignoring partition status when partition exists

[andy-maier]

When using the zhmc_partition module on systems that support the storage management feature, the partition needs to be created, then the storage group needs to be created and attached, and only then the partition can be started. The first step is supported by the zhmc_partition module by specifying state=stopped. However, that will stop the partition needlessly if it already exists.

A means is needed to ensure that:

• if the partition does not exist, it is created and is in stopped status
• if the partition exists, its properties are adjusted, but its status is left unchanged (except when a property update requires a stop/start sequence).

Proposal: Introduce a boolean parameter "ignore_status_when_present" to the zhmc_partition module.