build: Experimental support to build using precompiled headers

This type of build needs to be explicitly enabled using --with-pch
configure option.

Change-Id: I02dc304187d54c3cf40f1d51b1b11b21f868e225
diff --git a/src/node.cpp b/src/node.cpp
index 23e3185..0c9c872 100644
--- a/src/node.cpp
+++ b/src/node.cpp
@@ -5,6 +5,8 @@
  * See COPYING for copyright and distribution information.
  */
 
+#include "common.hpp"
+
 #include "node.hpp"
 
 #include "forwarding-entry.hpp"