LU-7734 lnet: fix lnet_peer_table_cleanup_locked()

LU-7734 lnet: fix lnet_peer_table_cleanup_locked()

In lnet_peer_table_cleanup_locked() we delete the entire peer if the
lnet_peer_ni for the primary NID of the peer is deleted. If the next
lnet_peer_ni in the list belongs to the peer being deleted, then the
next pointer kept by list_for_each_entry_safe() ends up pointing at
freed memory.

Add a list_for_each_entry_from() loop to advance next to a peer_ni
that does not belong to the peer being deleted and will therefore
remain present in the list.

Signed-off-by: Olaf Weber <olaf@sgi.com>
Change-Id: I92bf219dc93a79f7d90035ccfbb38cd251138c04
Reviewed-on: http://review.whamcloud.com/20824
Tested-by: Jenkins
Reviewed-by: Amir Shehata <amir.shehata@intel.com>
Tested-by: Amir Shehata <amir.shehata@intel.com>