patch 9.0.1302: on a Belgian keyboard CTRL-] does not work

Problem:    On a Belgian keyboard CTRL-] does not work.
Solution:   Translate CTRL-$ into CTRL-]. (closes #11831)

src/gui_x11.c

@@ -936,11 +936,11 @@ gui_x11_key_hit_cb(
     }
     else
     {
-	len = mb_char2bytes(key, string);
-
 	// Some keys need adjustment when the Ctrl modifier is used.
 	key = may_adjust_key_for_ctrl(modifiers, key);
 
+	len = mb_char2bytes(key, string);
+
 	// Remove the SHIFT modifier for keys where it's already included,
 	// e.g., '(', '!' and '*'.
 	modifiers = may_remove_shift_modifier(modifiers, key);