MRP-1361: synchronize MDS_INODELOCK_XATTR value with Intel

The final landing of MDS_INODELOCK_XATTR upstream used
MDS_INODELOCK_XATTR value of 0x20, the original code
should be updated with this value to be wire-compatible.

Change-Id: I870cf7b2765cfe0a7d686d0cb54e34c3837554b6
Reviewed-on: http://morpheus.xyus.xyratex.com:8443/gerrit/713
Tested-by: Jenkins
Reviewed-by: Andriy Skulysh <Andriy_Skulysh@xyratex.com>
Reviewed-by: Vitaly Fertman <Vitaly_Fertman@xyratex.com>
Tested-by: Elena Gryaznova <Elena_Gryaznova@xyratex.com>