; elisp-scope.el: Improve face specification handling.

Replace the use of 'elisp-scope-face(-1)' for analyzing face
specifications with 'elisp-scope-1' calls with an
appropriate OUTSPEC argument.  This allows us to analyze
face specifications even when they are not passed directly
to relevant functions, but rather appear in a tail position
of a form that evaluates to a face specification.

* lisp/emacs-lisp/elisp-scope.el
(elisp-scope--match-spec-to-arg): Add new 'face' spec.
Use it instead of...
(elisp-scope-face, elisp-scope-face-1): ...these functions.
Remove them, no longer used.

* test/lisp/progmodes/elisp-mode-resources/semantic-highlighting.el:
Add test.

test/lisp/progmodes/elisp-mode-resources/semantic-highlighting.el

@@ -171,3 +171,14 @@
   "Face for highlighting symbol role names in Emacs Lisp code."
   :version "31.1")
 ;; ^ (elisp-constant font-lock-builtin-face)
+
+(propertize foo
+            'face
+            (cond
+             ((random) '(success (:foreground "green" :inherit default)))
+;;                       ^ elisp-face
+;;                                                             ^ elisp-face
+             ((foobar) 'font-lock-keyword-face)
+;;                      ^ elisp-face
+             (t '(:inherit error))))
+;;                         ^ elisp-face