Clean prev source_loc impl leftovers

include/spdlog/common.h

@@ -202,29 +202,8 @@ private:
 };
 
 [[noreturn]] SPDLOG_API void throw_spdlog_ex(const std::string &msg, int last_errno);
-
 [[noreturn]] SPDLOG_API void throw_spdlog_ex(std::string msg);
 
-// trick to capture format string and caller's source location with variadic template.
-// see logger::info() etc. to understand how it's used.
-struct loc_with_fmt {
-    source_loc loc;
-    string_view_t fmt_string;
-
-    template <typename S, typename = is_convertible_to_sv<S>>
-    constexpr loc_with_fmt(S fmt_str, source_loc loc = source_loc::current()) noexcept
-        : loc(loc),
-          fmt_string(fmt_str) {}
-
-#ifndef SPDLOG_USE_STD_FORMAT
-
-    constexpr loc_with_fmt(fmt::runtime_format_string<char> fmt_str, source_loc loc = source_loc::current()) noexcept
-        : loc(loc),
-          fmt_string(fmt_str.str) {}
-
-#endif
-};
-
 struct file_event_handlers {
     file_event_handlers()
         : before_open(nullptr),