LU-10391 lnet: router_discover - handle large addrs in ping

LU-10391 lnet: router_discover - handle large addrs in ping

lnet_router_discover_ping_reply() now considers the large
nids in the ping message.

Test-Parameters: trivial testlist=sanity-lnet
Test-Parameters: serverversion=2.12 serverdistro=el7.9 testlist=runtests
Test-Parameters: clientversion=2.12 testlist=runtests
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: Ia67bcf2b09c976d9e4bf49a409e0d7bffe778ba4
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/44631
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Frank Sehr <fsehr@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>