bug#9239: 23.3.50; defmacro* doc-string bug

[Leo]

Eval:

(require 'cl)
(defmacro* xyz ((&optional keymap))
  "KEYMAP is not keymap")

Now try viewing the doc-string using C-h f xyz RET which should look
similar to:

i.e. the argument KEYMAP is not properly highlighted. Expect something
like:

Leo