[libcxx] Remove static inline and make use of _LIBCPP_HIDE_FROM_ABI in __support/xlocale/__nop_locale_mgmt.h header

[brad]

Summary

Remove static inline and make use of _LIBCPP_HIDE_FROM_ABI in the support/xlocale/nop_locale_mgmt.h header.

[Mordante]

This looks sensible to me. However I see a CI failure, can you rebase the patch and see whether it's a real failure or a glitch?

[brad]

Rebase.

[ldionne]

CI issues seem unrelated.

libcxx/include/__support/xlocale/__nop_locale_mgmt.h

 #define _LIBCPP_SUPPORT_XLOCALE_NOP_LOCALE_MGMT_H
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 // Patch over lack of extended locale support
 typedef void *locale_t;
-static inline locale_t duplocale(locale_t) {
+
+inline _LIBCPP_HIDE_FROM_ABI locale_t
+duplocale(locale_t) {
   return NULL;
 }
 
-static inline void freelocale(locale_t) {
+inline _LIBCPP_HIDE_FROM_ABI void
+freelocale(locale_t) {
 }
 
-static inline locale_t newlocale(int, const char *, locale_t) {
+inline _LIBCPP_HIDE_FROM_ABI locale_t
+newlocale(int, const char *, locale_t) {
   return NULL;
 }
 
-static inline locale_t uselocale(locale_t) {
+inline _LIBCPP_HIDE_FROM_ABI locale_t
+uselocale(locale_t) {
   return NULL;
 }
 
 #define LC_COLLATE_MASK  (1 << LC_COLLATE)
 #define LC_CTYPE_MASK    (1 << LC_CTYPE)
 #define LC_MESSAGES_MASK (1 << LC_MESSAGES)
 #define LC_MONETARY_MASK (1 << LC_MONETARY)
 #define LC_NUMERIC_MASK  (1 << LC_NUMERIC)