Added testcases for testing IPMI user privilege
Added testcases for testing IPMI user privilege

Test cases added:
    - Test IPMI user privilege level.
    - Test IPMI operator privilege level.
    - Test IPMI administrator privilege level.
    - Test IPMI no Access privilege level.

Change-Id: Idc4d1ba3b0fcf6085a48b6ab5e1d909499fdbc76
Signed-off-by: Rahul Maheshwari <a806e6fd77e56dd64ff6084a06bbf3a5a70392ef@in.ibm.com>

openbmc/openbmc-test-automation,openbmc/openbmc-test-automation