bug#28097: 26.0.50; Commit 9746058 breaks build on MS-Windows

[Chris Zheng <chriszheng99@gmail.com>]

The error message is

fileio.c: In function 'Frename_file':
fileio.c:2300:41: error: duplicate case value
  case EEXIST: case EINVAL: case ENOSYS: case ENOTSUP:
                                         ^~~~
fileio.c:2300:28: note: previously used here
  case EEXIST: case EINVAL: case ENOSYS: case ENOTSUP:
                            ^~~~

Because the file nt/inc/ms-w32.h, line 389, has the definition
“#define ENOTSUP ENOSYS” and it is included early than errno.h
which has the right define. One possible fix is is

@@ -2297,7 +2297,10 @@ This is what happens in interactive use with M-x.  */)
       rename_errno = errno;
       switch (rename_errno)
 	{
-	case EEXIST: case EINVAL: case ENOSYS: case ENOTSUP:
+	case EEXIST: case EINVAL: case ENOSYS:
+#ifdef DARWIN_OS
+	case ENOTSUP:
+#endif
 	  barf_or_query_if_file_exists (newname, rename_errno == EEXIST,
 					"rename to it",
 					INTEGERP (ok_if_already_exists),

Or we can change the #define in ms-w32.h.

Could you please have a look on it?

Thank you,
Chris