[newlib-cygwin] winsup: delete old _LIBC logic

[Michael Frysinger]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=24491c1251d4b8711ce5fa577e16ed01c46db7a6

commit 24491c1251d4b8711ce5fa577e16ed01c46db7a6
Author: Mike Frysinger <vapier@gentoo.org>
Date:   Tue Nov 9 19:25:22 2021 -0500

    winsup: delete old _LIBC logic
    
    This logic has never been used as we don't define _LIBC and the
    reentrant.h header doesn't exist, so delete it all.

Diff:
---
 winsup/cygwin/tzcode/private.h | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/winsup/cygwin/tzcode/private.h b/winsup/cygwin/tzcode/private.h
index 830750ad5..beae506d2 100644
--- a/winsup/cygwin/tzcode/private.h
+++ b/winsup/cygwin/tzcode/private.h
@@ -777,19 +777,4 @@ char *ctime_r(time_t const *, char *);
   ((int_fast64_t) YEARSPERREPEAT * (int_fast64_t) AVGSECSPERYEAR)
 #define SECSPERREPEAT_BITS	34	/* ceil(log2(SECSPERREPEAT)) */
 
-#ifdef _LIBC
-#include "reentrant.h"
-extern struct __state *__lclptr;
-#if defined(__LIBC12_SOURCE__)
-#define tzset_unlocked __tzset_unlocked
-#else
-#define tzset_unlocked __tzset_unlocked50
-#endif
-
-void tzset_unlocked(void);
-#ifdef _REENTRANT
-extern rwlock_t __lcl_lock;
-#endif
-#endif
-
 #endif /* !defined PRIVATE_H */