Prevent updating power cap sysfs file when OCC not active

The power cap can be updated at any time, but occ-control should only
update the sysfs files when the OCCs are active.
Also prevent sending pass through commands when OCC is not
active.

Change-Id: I7e5d5ad0b897b55a00e4d07c62b917aa62b7f9ef
Signed-off-by: Chris Cain <cjcain@us.ibm.com>
3 files changed