Applied queue fix in 802.11 mac (discovered by RK)

src/de/tud/kom/p2psim/impl/linklayer/mac/wifi/Ieee80211AdHocMac.java

@@ -288,10 +288,9 @@ public class Ieee80211AdHocMac extends AbstractMacLayer {
 	 * reseted to 0.
 	 */
 	protected void sendNextMessage() {
-		toSend = null;
+		toSend = getQueueHead();
 		retryCounter = 0;
-		if (getQueueSize() > 0) {
-			toSend = getQueueHead();
+		if (toSend != null) {
 			sendMessage();
 		}
 	}