LU-11605 osp: max_create_count and create_count changes

LU-11605 osp: max_create_count and create_count changes

Setting max_create_count to 0 causes setting create_count
to 0. Set create_count to OST_MIN_PRECREATE when setting
back max_create_count.
Without the patch create_count remains equal to 0 despite
on changing max_create_count to something != 0.
This causes create to stuck in osp_precreate_reserve
because osp_precreate_send doesn't send new request to OST.
To understand the number of objects to precreate(grow) it
uses opd_pre_create_count that is equal to 0.

Cray-bug-id: LUS-6435
Change-Id: I940c48f91e9c7d49b766bd85ea271ce229424c7f
Signed-off-by: Sergey Cheremencev <c17829@cray.com>
Reviewed-on: https://es-gerrit.dev.cray.com/153888
Reviewed-by: Alexander Zarochentsev <c17826@cray.com>
Reviewed-by: Artem Blagodarenko <c17828@cray.com>
Tested-by: Elena Gryaznova <c17455@cray.com>
Reviewed-on: https://review.whamcloud.com/33559
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>