LU-13363 lod: do object allocation in OST pool

LU-13363 lod: do object allocation in OST pool

Currently, the ltd->ltd_qos.lq_same_space boolean that decides
whether the LOD QOS allocator is active for an allocation or not
is tracked for the entire LOV. But when a pool is specified, this
judgement should be tracked on a per-pool basis.

sanity.sh test_116c is added to verify this patch.

Test-Parameters: ostcount=6 testlist=sanity env=ONLY=116c
Signed-off-by: Emoly Liu <emoly@whamcloud.com>
Change-Id: I463d5927c7a9c9171483615d2cec629ec10dc666
Reviewed-on: https://review.whamcloud.com/38136
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>