LU-7851 mdt: skip SOM related configuration

LU-7851 mdt: skip SOM related configuration

the SOM is deprecated, then the old SOM configuration should be
skipped by the newer version when upgrading Lustre.

Change-Id: Ibb32e43501479aac75c8e02a652bea8d8a727445
Signed-off-by: Hongchao Zhang <hongchao.zhang@intel.com>
Reviewed-on: http://review.whamcloud.com/18834
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>