wireproto: only advertise HTTP-specific capabilities to HTTP peers (BC)
Previously, the capabilities list was protocol agnostic and we
advertised the same capabilities list to all clients, regardless of
transport protocol.
A few capabilities are specific to HTTP. I see no good reason why we
should advertise them to SSH clients. So this patch limits their
advertisement to HTTP clients.
This patch is BC, but SSH clients shouldn't be using the removed
capabilities so there should be no impact.