option missval now uses string_to_floating

src/cdo_def_options.cc

@@ -328,7 +328,7 @@ setup_options()
   CLIOptions::option("set_missval", "m")
       ->describe_argument("missval")
       ->add_effect([&](const std::string &argument) {
-        auto [success, mv] = string_to_number<double>(argument);
+        auto [success, mv] = string_to_floating<double>(argument);
         if (success)
           {
             Debug("set missval of cdi to: %f", mv);