The entries with '- ESTAB' are the assocs, some of them may belong to
the same endpoint. So we will dump the parent endpoint first, like the
entry with 'LISTEN'. then dump the assocs. ep and assocs entries will
be dumped in right order so that ss can show them in tree format easily.
Besides, this patchset also simplifies sctp proc codes, cause it has
some similar codes with sctp diag in sctp transport traversal.
v1->v2:
1. inet_diag_get_handler needs to return it as const.
2. merge 5/7 into 2/7 of v1.
v2->v3:
do some improvements and fixes in patch 1-4, see the details in
each patch's comment.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>