LU-5188 osp: return 1 if osp_sync_xxx_job issue RPC

Return 1 if osp_sync_new_xxx_job() issue RPC, so
sp_sync_process_record() can decrease opd_syn_rpc_in_flight
and opd_syn_rpc_in_progress correctly if RPC is not
being sent, otherwise the opd_sync_thread will not be
stopped, caused LBUG (see LU-5244)

osp_sync_thread()) ASSERTION( count < 10 ) failed:

The problem is introduced by

http://review.whamcloud.com/10706

Change-Id: Iaf6dd6c4e1938a0c5d44a40c303eda1695b72105
Signed-off-by: Wang Di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/10828
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>