configure.in: don't check for existence of timezone()

HAVE_TIMEZONE and TIMEZONE_VOID macros are not used anymore as of r28592
("strftime.c: unused declarations removed.", 2010-07-09).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59938 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

configure.in

@@ -2834,18 +2834,6 @@ AS_IF([test "${AS_TR_SH(rb_cv_var_$1)}" != no], [
 ])])
 RUBY_CHECK_VARTYPE(timezone, [@%:@include <time.h>], [long int])
 RUBY_CHECK_VARTYPE(altzone, [@%:@include <time.h>], [long int])
-AC_CHECK_FUNCS(timezone)
-AS_IF([test "$ac_cv_func_timezone" = yes], [
-  AC_CACHE_CHECK([whether timezone requires zero arguments], rb_cv_func_timezone_void,
-    [AC_TRY_COMPILE([@%:@include <time.h>],
-      [(void)timezone(0, 0);],
-      [rb_cv_func_timezone_void=no],
-      [rb_cv_func_timezone_void=yes])]
-  )
-  AS_IF([test $rb_cv_func_timezone_void = yes], [
-    AC_DEFINE(TIMEZONE_VOID)
-  ])
-])
 
 AC_CACHE_CHECK(for negative time_t for gmtime(3), rb_cv_negative_time_t,
   [AC_TRY_RUN([