ftests: Add cgget '-a' test

ftests: Add cgget '-a' test

Add a cgget test that utilizes the '-a' flag.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Feb 11 19:27:39
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                    Time (sec)
        ---------------------------------------------------------
        setup                                        20.61
        014-cgget-a_flag.py                           1.01
        teardown                                      0.00
        ---------------------------------------------------------
        Total Run Time                               21.62

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