Bind more unbound keys in viins and vicmd to nothing

Unbound keys in viins or vicmd mode have undefined results. Bind
two more of these to nothing to avoid this.

modules/editor/init.zsh

@@ -31,6 +31,8 @@ key_info=(
   'Control'         '\C-'
   'ControlLeft'     '\e[1;5D \e[5D \e\e[D \eOd'
   'ControlRight'    '\e[1;5C \e[5C \e\e[C \eOc'
+  'ControlPageUp'   '\e[5;5~'
+  'ControlPageDown' '\e[6;5~'
   'Escape'       '\e'
   'Meta'         '\M-'
   'Backspace'    "^?"
@@ -305,6 +307,8 @@ unbound_keys=(
   "${key_info[F12]}"
   "${key_info[PageUp]}"
   "${key_info[PageDown]}"
+  "${key_info[ControlPageUp]}"
+  "${key_info[ControlPageDown]}"
 )
 for keymap in $unbound_keys; do
   bindkey -M viins "${keymap}" _prezto-zle-noop