* winlean.h: Make sure certain Windows macros are undefined again.

Add comment to explain why.
	* winsup.h: Include winlean.h from C sources as well.
	* libc/minires-os-if.c: Drop including ntdef.h.

	Fix previous ChangeLog entry.

winsup/cygwin/winsup.h

@@ -81,8 +81,12 @@ int fcntl64 (int fd, int cmd, ...);
 #define __WIDE(a) L ## a
 #define _WIDE(a) __WIDE(a)
 
+#include "winlean.h"
+
 #ifdef __cplusplus
 
+#include "wincap.h"
+
 extern const char case_folded_lower[];
 #define cyg_tolower(c) (case_folded_lower[(unsigned char)(c)])
 extern const char case_folded_upper[];
@@ -92,9 +96,6 @@ extern const char case_folded_upper[];
 #define cfree newlib_cfree_dont_use
 #endif
 
-#include "winlean.h"
-#include "wincap.h"
-
 /* Used as type by sys_wcstombs_alloc and sys_mbstowcs_alloc.  For a
    description see there. */
 #define HEAP_NOTHEAP -1