refactor: use std::string in tr_info (#2384)

libtransmission/utils.h

@@ -164,13 +164,6 @@ std::optional<T> tr_parseNum(std::string_view& sv)
 
 #endif // #if defined(__GNUC__) && !__has_include(<charconv>)
 
-/**
- * @brief make a copy of 'str' whose non-utf8 content has been corrected or stripped
- * @return a newly-allocated string that must be freed with tr_free()
- * @param str the string to make a clean copy of
- */
-char* tr_utf8clean(std::string_view str) TR_GNUC_MALLOC;
-
 bool tr_utf8_validate(std::string_view sv, char const** endptr);
 
 #ifdef _WIN32
@@ -300,6 +293,14 @@ std::string tr_strlower(T in)
     return out;
 }
 
+template<typename T>
+std::string tr_strupper(T in)
+{
+    auto out = std::string{ in };
+    std::for_each(std::begin(out), std::end(out), [](char& ch) { ch = std::toupper(ch); });
+    return out;
+}
+
 /***
 ****  std::string_view utils
 ***/