don't create SSU session if endpoint is not specified. Wait from RelayResponse

libi2pd/SSU.cpp

@@ -433,7 +433,7 @@ namespace transport
 			{
 				boost::asio::ip::udp::endpoint remoteEndpoint (address->host, address->port);
 				auto it = m_Sessions.find (remoteEndpoint);
-				// check if session if presented alredy
+				// check if session is presented already
 				if (it != m_Sessions.end ())
 				{	
 					auto session = it->second;
@@ -480,9 +480,14 @@ namespace transport
 						introducerSession = std::make_shared<SSUSession> (*this, introducerEndpoint, router);
 						m_Sessions[introducerEndpoint] = introducerSession;													
 					}
+#if BOOST_VERSION >= 104900					
+					if (!address->host.is_unspecified () && address->port)
+#endif
+					{
 						// create session	
 						auto session = std::make_shared<SSUSession> (*this, remoteEndpoint, router, peerTest);
 						m_Sessions[remoteEndpoint] = session;
+
 						// introduce
 						LogPrint (eLogInfo, "SSU: Introduce new session to [", i2p::data::GetIdentHashAbbreviation (router->GetIdentHash ()),
 								"] through introducer ", introducer->iHost, ":", introducer->iPort);
@@ -492,6 +497,7 @@ namespace transport
 							uint8_t buf[1];
 							Send (buf, 0, remoteEndpoint); // send HolePunch
 						}	
+					}
 					introducerSession->Introduce (*introducer, router);
 				}
 				else