[Bugfix] Don't compile gethomedir function on WIN32

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4178 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/os/os.cxx b/common/os/os.cxx
index 8d24875..5d41055 100644
--- a/common/os/os.cxx
+++ b/common/os/os.cxx
@@ -20,6 +20,7 @@
 #include <config.h>
 #endif
 
+#ifndef WIN32
 #include <os/os.h>
 
 #include <assert.h>
@@ -62,3 +63,5 @@
 	return 0;
 }
 
+#endif
+