Replaced a few more 0xffffffff by the appropriate constants.

programs/notepad/dialog.c

diff --git a/programs/notepad/dialog.c b/programs/notepad/dialog.c
index d6a6f4b..7cbee4f 100644
--- a/programs/notepad/dialog.c
+++ b/programs/notepad/dialog.c
@@ -222,7 +222,7 @@
     }
 
     size = GetFileSize(hFile, NULL);
-    if (size == 0xFFFFFFFF)
+    if (size == INVALID_FILE_SIZE)
     {
 	CloseHandle(hFile);
 	ShowLastError();