LU-9330 osp: make variables match proc tunables

LU-9330 osp: make variables match proc tunables

Make the osp_syn_* and osp_max_rpcs_* function names consistent with
the tunable names in proc so that they are easier to find.

osp_max_rpcs_in_prog_seq_show()->osp_max_rpcs_in_progress_seq_show()
osp_max_rpcs_in_prog_seq_write()->osp_max_rpcs_in_progress_seq_write()
osp_syn_changes_seq_show()->osp_sync_changes_seq_show()
osp_syn_changes_seq_write()->osp_sync_changes_seq_write()
osp_syn_in_flight_seq_show()->osp_sync_rpcs_in_flight_seq_show()
osp_syn_in_prog_seq_show()->osp_sync_rpcs_in_progress_seq_show()

This entails renaming the osp_syn_* function names consistent with the
function names, so change _syn_ -> _sync_, _prog_ -> _progress_,
and _rpc_ -> _rpcs_.

Make osp_sync_check_for_work() a proper function rather than having
both a macro and __osp_sync_check_for_work() as a function that just
calls the macro.

Remove unused field opd_syn_sync_in_progress.

Test-Parameters: trivial
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Change-Id: I537e04fdce7eea194f1a9567b6e5c3ccee2cab07
Reviewed-on: https://review.whamcloud.com/26571
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Emoly Liu <emoly.liu@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>