use splice if queue is not semi-full

libi2pd/SSU2Session.cpp

@@ -412,9 +412,11 @@ namespace transport
 					" is semi-full (size = ", m_SendQueue.size (), ", lag = ", queueLag / 1000, ", rtt = ", (int)m_RTT, ")");
 			}
 		}
+		if (isSemiFull)
+		{	
 			for (auto it: msgs)
 			{
-			if (isSemiFull && it->onDrop)
+				if (it->onDrop)
 					it->Drop (); // drop earlier because we can handle it
 				else
 				{
@@ -422,6 +424,12 @@ namespace transport
 					m_SendQueue.push_back (std::move (it));
 				}
 			}
+		}	
+		else
+		{
+			for (auto& it: msgs) it->SetEnqueueTime (mts);
+			m_SendQueue.splice (m_SendQueue.end (), msgs);
+		}	
 		if (IsEstablished ())
 		{	
 			SendQueue ();