LU-4167 tests: update version check to conf-sanity test_32

LU-4167 tests: update version check to conf-sanity test_32

This patch updates version check codes to skip running LFSCK on an
OST for versions >= 2.5.0 in conf-sanity.sh test_32.

Test-Parameters: testlist=conf-sanity envdefinitions=SLOW=yes, ONLY=32 ossjob=lustre-b2_4 mdsjob=lustre-b2_4 ossbuildno=71 mdsbuildno=71 clientdistro=el6 ossdistro=el6 mdsdistro=el6 clientarch=x86_64 ossarch=x86_64 mdsarch=x86_64
Signed-off-by: Emoly Liu <emoly.liu@intel.com>
Change-Id: Ibc0c34a0c15f4882a0dd06dae75d1f1fe10b6f16
Reviewed-on: http://review.whamcloud.com/8132
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>