Include correct feature fixed_int.

tests/feature/fixed_int/generate_fixed_uint_multiplications.cc

@@ -247,7 +247,7 @@ void generate_mul_file()
     file << "#include <x86intrin.h>\n";
     file << "#endif\n\n";
 
-    file << "#include <typed-geometry/feature/fixed_uint.hh>\n\n";
+    file << "#include <typed-geometry/feature/fixed_int.hh>\n\n";
     file << "namespace tg::detail\n{\n";
     file << "template <int w_res, class T0, class T1>\n";
     file << "fixed_uint<w_res> mul(T0 const& lhs, T1 const& rhs);\n\n";