LU-6256 test: Skip sanity test_184e if MDS version older than 2.6.94

LU-6256 test: Skip sanity test_184e if MDS version older than 2.6.94

Skip sanity test_184e if MDS version older than 2.6.94

Change-Id: Ib491b079a3adc998a12d9bbcb7985ad2e718453b
Signed-off-by: Wei Liu <wei3.liu@intel.com>
Reviewed-on: http://review.whamcloud.com/13845
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>