LU-4536 ldlm: Recalculate interval in ldlm_pool_recalc()

Instead of rechecking a static value, recalculate to see if pool stats
need to be updated.
Add newline so message will print instead of warning about missing
newline.

Test-Parameters: mdsfilesystemtype=zfs mdtfilesystemtype=zfs ostfilesystemtype=zfs testlist=sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity,sanity
Signed-off-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Change-Id: Ic31cc0c1d09a85a9bd5ee04ac34c388263190df1
Reviewed-on: http://review.whamcloud.com/12547
Tested-by: Jenkins
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jian Yu <jian.yu@intel.com>