LU-2689 interop: use stripe md in ll_update_inode()

LU-2689 interop: use stripe md in ll_update_inode()

When connected to servers that do not support LL_SBI_LAYOUT_LOCK, if
stripe md is available in ll_inode_update() then use it.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I949a0129c3fc92c5434288df0549a54ccd440f97
Reviewed-on: http://review.whamcloud.com/5289
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>