Revert "import code for fmtlib 11.1.0"

This reverts commit 833607f926.

src/fmtlib_format.cpp

@@ -16,8 +16,7 @@ template FMT_API auto dragonbox::to_decimal(float x) noexcept
 template FMT_API auto dragonbox::to_decimal(double x) noexcept
     -> dragonbox::decimal_fp<double>;
 
-#if FMT_USE_LOCALE
-// DEPRECATED! locale_ref in the detail namespace
+#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
 template FMT_API locale_ref::locale_ref(const std::locale& loc);
 template FMT_API auto locale_ref::get<std::locale>() const -> std::locale;
 #endif
@@ -28,10 +27,8 @@ template FMT_API auto thousands_sep_impl(locale_ref)
     -> thousands_sep_result<char>;
 template FMT_API auto decimal_point_impl(locale_ref) -> char;
 
-// DEPRECATED!
 template FMT_API void buffer<char>::append(const char*, const char*);
 
-// DEPRECATED!
 template FMT_API void vformat_to(buffer<char>&, string_view,
                                  typename vformat_args<>::type, locale_ref);