LU-7012 osp: don't use OSP when import is deactivated

LU-7012 osp: don't use OSP when import is deactivated

Unset opd_imp_connected flag upon IMP_EVENT_INACTIVE event,
it will stop any llog processing by that device until import
will be activated again.

Signed-off-by: Mikhail Pershin <mike.pershin@intel.com>
Change-Id: Ie219e536c216130f428ba933d11842511692c95b
Reviewed-on: http://review.whamcloud.com/16937
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Jian Yu <jian.yu@intel.com>
Tested-by: Jenkins
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>