libstdc++: Adjust std::in_range template parameter name

This is more consistent with the specification in the standard.

libstdc++-v3/ChangeLog:

	* include/std/utility (in_range): Rename _Up parameter to _Res.

libstdc++-v3/include/std/utility

@@ -171,22 +171,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     cmp_greater_equal(_Tp __t, _Up __u) noexcept
     { return !std::cmp_less(__t, __u); }
 
-  template<typename _Up, typename _Tp>
+  template<typename _Res, typename _Tp>
     constexpr bool
     in_range(_Tp __t) noexcept
     {
-      static_assert(__is_standard_integer<_Up>::value);
+      static_assert(__is_standard_integer<_Res>::value);
       static_assert(__is_standard_integer<_Tp>::value);
       using __gnu_cxx::__int_traits;
 
-      if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
-	return __int_traits<_Up>::__min <= __t
-	  && __t <= __int_traits<_Up>::__max;
+      if constexpr (is_signed_v<_Tp> == is_signed_v<_Res>)
+	return __int_traits<_Res>::__min <= __t
+	  && __t <= __int_traits<_Res>::__max;
       else if constexpr (is_signed_v<_Tp>)
 	return __t >= 0
-	  && make_unsigned_t<_Tp>(__t) <= __int_traits<_Up>::__max;
+	  && make_unsigned_t<_Tp>(__t) <= __int_traits<_Res>::__max;
       else
-	return __t <= make_unsigned_t<_Up>(__int_traits<_Up>::__max);
+	return __t <= make_unsigned_t<_Res>(__int_traits<_Res>::__max);
     }
 #endif // __cpp_lib_integer_comparison_functions