Add __nl_item to <sys/_types.h> and use it

Add __nl_item to <sys/_types.h> for FreeBSD compatibility.  Use it in
<langinfo.h> and the Cygwin <nl_types.h>.  Make the enum __nl_item in
<langinfo.h> anonymous.

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>

newlib/libc/include/langinfo.h

@@ -29,19 +29,18 @@
 #ifndef _LANGINFO_H_
 #define	_LANGINFO_H_
 
-#include <newlib.h>
-#include <sys/config.h>
 #include <sys/cdefs.h>
+#include <sys/_types.h>
 #if __POSIX_VISIBLE >= 200809
 #include <xlocale.h>
 #endif
 
 #ifndef _NL_ITEM_DECLARED
-typedef int nl_item;
+typedef __nl_item nl_item;
 #define _NL_ITEM_DECLARED
 #endif
 
-enum __nl_item
+enum
 {
   /* POSIX and BSD defined items have to stick to the original values
      to maintain backward compatibility. */

newlib/libc/include/sys/_types.h

@@ -210,6 +210,7 @@ typedef	__uint8_t	__sa_family_t;
 typedef	__uint32_t	__socklen_t;
 #endif
 
+typedef	int		__nl_item;
 typedef	unsigned short	__nlink_t;
 typedef	long		__suseconds_t;	/* microseconds (signed) */
 typedef	unsigned long	__useconds_t;	/* microseconds (unsigned) */

winsup/cygwin/include/nl_types.h

@@ -87,7 +87,7 @@ typedef struct __nl_cat_d {
 
 
 #ifndef _NL_ITEM_DECLARED
-typedef int nl_item;
+typedef __nl_item nl_item;
 #define _NL_ITEM_DECLARED
 #endif