Added test cases to verify turbo allowed value.

This change includes:
   - Added test cases to verify enable and disable turbo
     allowed via IPMI.
   - Added suite teardown to restore system configuration.
   - Added this test case in skip lists of NA system.

Resolves openbmc/openbmc-test-automation#527

Change-Id: Ifd1e7d93ceb699731e211b1856a5574a9d0fbe17
Signed-off-by: Rahul Maheshwari <rahulmaheshwari@in.ibm.com>
4 files changed