Seeder dumps incorrect service flags under these circumstances:
1. When a seed node is provided manually with -overridednsseed
2. When a seed node address is fetched from other seeders
The service flags may be corrected only if the node is re-rumored via getaddr by some other node. This does not happen for situation 1 above unless the node is public facing.
This patch makes version messages set the service bits correctly.
This is a backport of https://github.com/sipa/bitcoin-seeder/commit/a1e93942842316b60685008f589290d5bdde2058