fix klockwork issues

Add return 0 for int main()

Signed-off-by: Zhikui Ren <zhikui.ren@intel.com>
Change-Id: I4ff6ef571827b17b89ed653c420e7f9964ab42f5
diff --git a/src/FanMain.cpp b/src/FanMain.cpp
index 30f0ca4..465ce1b 100644
--- a/src/FanMain.cpp
+++ b/src/FanMain.cpp
@@ -527,4 +527,5 @@
 
     setupManufacturingModeMatch(*systemBus);
     io.run();
+    return 0;
 }