Correction of trivial warnings.

git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@4670 19bc5d8c-e614-43d4-8b26-e1612bc8e597
diff --git a/Transceiver52M/DummyLoad.cpp b/Transceiver52M/DummyLoad.cpp
index d11226e..38718a0 100644
--- a/Transceiver52M/DummyLoad.cpp
+++ b/Transceiver52M/DummyLoad.cpp
@@ -97,11 +97,11 @@
   underrunLock.unlock();
   if (currstamp+len < timestamp) {
 	usleep(100); 
-	return NULL;
+	return 0;
   } 
   else if (currstamp < timestamp) {
 	usleep(100);
-	return NULL;
+	return 0;
   }
   else if (timestamp+len < currstamp) {
 	memcpy(buf,dummyBurst+dummyBurstCursor*2,sizeof(short)*2*(dummyBurstSz-dummyBurstCursor));