LU-10391 lnet: Change lnet_send() to take large-addr nids

LU-10391 lnet: Change lnet_send() to take large-addr nids

The src and rtr nids passed to lnet_send() are now pointers to a
'struct lnet_nid'.  NULL can be passed for the rtr nid, which is
treated the same as ANY.

Test-Parameters: trivial
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: Id216b82ed6e2dcd81114859a7f964e0680057ff1
Reviewed-on: https://review.whamcloud.com/43599
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>