connectd: don't use gossip_getnodes_entry.

gossip_getnodes_entry was used by gossipd for reporting nodes, and for
reporting peers.  But the local_features field is only available for peers,
and most other fields are only available from node_announcement.

Note that the connectd change actually means we get less information
about peers: gossipd used to do the node lookup for peers and include the
node_announcement information if it had it.

Since generate_wire.py can't create arrays-of-arrays, we add a 'struct
peer_features' to encapsulate the two feature arrays for each peer, and
for convenience we add it to lightningd/gossip_msg.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

tools/generate-wire.py

@@ -31,6 +31,7 @@ type2size = {
 
 # These struct array helpers require a context to allocate from.
 varlen_structs = [
+    'peer_features',
     'gossip_getnodes_entry',
     'failed_htlc',
     'utxo',