Remove some non-canonical local pools from FSFS stats code.

* subversion/libsvn_fs_fs/stats.c
  (parse_dir,
   read_noderev): Remove sub-pools that don't reduce peak allocation
                  assuming that the SCRATCH_POOL gets cleaned up by
                  read_noderev's caller.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1639440 13f79535-47bb-0310-9956-ffa450edef68