s4-librpc: Fix netlogon schannel client connect.

As a client we request as much flags as possible. The server checks
which flags it supports and returns the same negotiation flags or less.
So we need to store the negotiate flags from the server. We need them
later if we have to call netr_LogonGetCapabilities.

source4/librpc/rpc/dcerpc_schannel.c

@@ -245,6 +245,8 @@ static void continue_srv_auth2(struct tevent_req *subreq)
 		return;
 	}
 
+	s->creds->negotiate_flags = s->remote_negotiate_flags;
+
 	/* verify credentials */
 	if (!netlogon_creds_client_check(s->creds, s->a.out.return_credentials)) {
 		composite_error(c, NT_STATUS_UNSUCCESSFUL);