ftests: Add a cgxget/cgxset test for the cpu controller

ftests: Add a cgxget/cgxset test for the cpu controller

Add a functional test that exercises the cpu v1/v2 mappings.

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Test Results:
        Run Date:                          Apr 19 18:39:16
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                    Time (sec)
        ---------------------------------------------------------
        setup                                         0.00
        037-cgxget-cpu_settings.py                    0.50
        teardown                                      0.00
        ---------------------------------------------------------
        Total Run Time                                0.50

Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>