Make sure Windows specific code is only included in Windows builds.
Patch by Henrik Andersson.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4334 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/rfb/CMakeLists.txt b/common/rfb/CMakeLists.txt
index 7679437..d043049 100644
--- a/common/rfb/CMakeLists.txt
+++ b/common/rfb/CMakeLists.txt
@@ -59,12 +59,15 @@
   UpdateTracker.cxx
   VNCSConnectionST.cxx
   VNCServerST.cxx
-  WinPasswdValidator.cxx	# Windows specific code
   ZRLEEncoder.cxx
   ZRLEDecoder.cxx
   encodings.cxx
   util.cxx)
 
+if(WIN32)
+  set(RFB_SOURCES ${RFB_SOURCES} WinPasswdValidator.cxx)
+endif(WIN32)
+
 set(RFB_LIBRARIES ${JPEG_LIBRARIES} os)
 
 if(GNUTLS_FOUND)