fixing VC6 build bustage

xpcom/ds/nsWindowsRegKey.cpp

@@ -43,6 +43,12 @@
 #include "nsString.h"
 #include "nsCOMPtr.h"
 
+// The Platform SDK included with VC6 does not define REG_QWORD.  VC 7's
+// WinNT.h defines REG_QWORD as follows:
+#ifndef REG_QWORD
+# define REG_QWORD 11
+#endif
+
 //-----------------------------------------------------------------------------
 
 // This class simplifies conversion from unicode to native charset somewhat.