Don't duplicate INVALID_FILE_ATTRIBUTES definition.

Move it in wx/msw/missing.h header instead of defining it in two different
places.

Closes #12964.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66996 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/missing.h

@@ -537,5 +537,9 @@ typedef struct
     #endif
 #endif  // defined __WINE__
 
+#ifndef INVALID_FILE_ATTRIBUTES
+    #define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
+#endif
+
 #endif
     // _WX_MISSING_H_

src/common/filefn.cpp

@@ -98,10 +98,6 @@
     #define _MAXPATHLEN 1024
 #endif
 
-#ifndef INVALID_FILE_ATTRIBUTES
-    #define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
-#endif
-
 // ----------------------------------------------------------------------------
 // private globals
 // ----------------------------------------------------------------------------

src/common/filename.cpp

@@ -153,13 +153,6 @@
 extern const wxULongLong wxInvalidSize = (unsigned)-1;
 #endif // wxUSE_LONGLONG
 
-#ifdef __WIN32__
-    // this define is missing from VC6 headers
-    #ifndef INVALID_FILE_ATTRIBUTES
-        #define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
-    #endif
-#endif // __WIN32__
-
 namespace
 {