LU-10391 lnet: convert nids in lnet_parse to lnet_nid

LU-10391 lnet: convert nids in lnet_parse to lnet_nid

src_nid and dest_nid in lnet_parse() are changed to
struct lnet_nid, and this change propagates out to
affect a few support function.

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: Ic6922d3f643e493f92f8f64974ad30f66457e842
Reviewed-on: https://review.whamcloud.com/43613
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>