roster: redirect the FIFA 17 roster dial at the socket

FIFA 17's ProtoSSL verifies the roster certificate by dNSName only, so an
IP-addressed roster host is refused even with the IP in the SANs. The hostname
therefore has to survive into SNI while the connection lands on our server.

The connect/WSAConnect/ConnectEx detour already intercepted the dial; it just
did not rewrite it, because 8081 was absent from the EA port table. Adding
ea_ports::FIFA17_ROSTER plus an OpenFutPorts.roster destination makes the
existing, proven redirect handle it with no new hook surface, and removes the
need for any client-side DNS change.

to_cfg_string writes roster_port ONLY when it differs from the default: the
parser rejects unknown keys, so emitting it unconditionally would make an
already-deployed older hook reject the whole config and install no redirect at
all -- breaking the game instead of degrading.

src/config.rs

@@ -326,6 +326,7 @@ impl LauncherConfig {
                 blaze_redirector: self.openfut_blaze_redirector_port,
                 blaze_main: self.openfut_blaze_main_port,
                 fut_content: openfut_common::default_ports::FUT_CONTENT,
+                roster: openfut_common::default_ports::ROSTER,
             },
         }
     }