LU-12930 various: use schedule_timeout_*interruptible

LU-12930 various: use schedule_timeout_*interruptible

The construct:

  set_current_state(TASK_UNINTERRUPTIBLE);
  schedule_timeout(time);

Is more clearly expressed as

  schedule_timeout_uninterruptible(time);

And similarly with TASK_INTERRUPTIBLE /
schedule_timeout_interruptible()

Establishing this practice makes it harder to forget to call
set_current_state() as has happened a couple of times - in
lnet_peer_discovery and mdd_changelog_fini().

Also, there is no need to set_current_state(TASK_RUNNABLE) after
calling schedule*().  That state is guaranteed to have been set.

In mdd_changelog_fini() there was an attempt to sleep for
10 microseconds.  This will always round up to 1 jiffy, so
just make it schedule_timeout_uninterruptible(1).

Finally a few places where the number of seconds was multiplied
by 1, have had the '1 *' removed.

Test-Parameters: trivial
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: I01b37039de0bf7e07480de372c1a4cfe78a8cdd8
Reviewed-on: https://review.whamcloud.com/36656
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>