On unmarshal, we stop unmarshaling on a 0 (ADDR_TYPE_PADDING) type. So
we should also stop marshaling in that case.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In future it will have TOR support, so the name will be awkward.
We collect the to/fromwire functions in common/wireaddr.c, and the
parsing functions in lightningd/netaddress.c.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>