LU-13307 nodemap: have nodemap_add_member support large NIDs

LU-13307 nodemap: have nodemap_add_member support large NIDs

Currently when mounting lustre using IPv6 address fails with

Lustre: 27361:0:(nodemap_handler.c:395:nodemap_add_member())
  lustre-MDT0000: error adding to nodemap, no valid NIDs found
LustreError: 11-0: lustre-MDT0000-osp-MDT0003:
  operation mds_connect to node 0@lo failed: rc = -22

This was due to no nodemap being set so the ptlrpc layer was not
seeing any new peers. Adding minimal support to nodemap allows
mounting.

Change-Id: If9cfe88ec92afc3f14788f3f3ded8387a1b5d8c7
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53135
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>