Fix small bug on config window

If the default language was active and a different language was selected and then the "Cancel" button was pressed, next time the config window was open it would still display the selected language even though it didn't actually change.

src/window/config.c

@@ -233,6 +233,7 @@ static void init(void)
     string_copy(translation_for(TR_CONFIG_LANGUAGE_DEFAULT), data.language_options_data[0], CONFIG_STRING_VALUE_MAX);
     data.language_options[0] = data.language_options_data[0];
     data.num_language_options = 1;
+    data.selected_language_option = 0;
     const dir_listing *subdirs = dir_find_all_subdirectories();
     const char *original_value = data.config_string_values[CONFIG_STRING_UI_LANGUAGE_DIR].original_value;
     for (int i = 0; i < subdirs->num_files; i++) {