Step: set_part_flag
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Set or clear a flag in a partition.

Step keys:

* `set_part_flag` &mdash; REQUIRED; filename of block device containing
  partition that will have the flag set or cleared.

* `tag` &mdash; REQUIRED; tag of the partition being modified.

* `flag` &mdash; REQUIRED; the name of the flag to be set or cleared

* `state` &mdash; OPTIONAL; the flag state: "enabled" or "disabled". Defaults
  to "enabled".

Example (in the .vmdb file):

    - set_part_flag: "{{ output }}"
      tag: rootfs
      flag: bios_grub
      state: enabled
