LU-8378 obd: move s3 in lmd_parse to inner loop

LU-8378 obd: move s3 in lmd_parse to inner loop

The upstream client complains with:

obdclass/obd_mount.c: In function lmd_parse:
obdclass/obd_mount.c:880: warning: variable set but not used

The solution is to move s3 to the inner loop
where it is only used.

Test-Parameters: trivial

Change-Id: I95280d08e5f00cf5fdae62acb21e2c08805a9948
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/23820
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>