LU-8357 nodemap: reclassify nodemap requires active conf lock

LU-8357 nodemap: reclassify nodemap requires active conf lock

A couple of call paths did not take the lock, which led to race
conditions. This patch ensures that those calls are under lock.

Signed-off-by: Kit Westneat <kit.westneat@gmail.com>
Change-Id: I3db8203b0b6d7d02a02cbe1c3ed6c847915d0076
Reviewed-on: http://review.whamcloud.com/21159
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>