C Mode: Don't fontify foo globally as type due to "struct foo"

This fixes bug#64322.

* lisp/progmodes/cc-langs.el (c-typeless-decl-kwds): Make the
entry for c-mode nil.

lisp/progmodes/cc-fonts.el

@@ -2240,7 +2240,7 @@ on level 2 only and so aren't combined with `c-complex-decl-matchers'."
 		     (c-forward-syntactic-ws))
 		   (goto-char (match-end ,type-match))))))))
 
-      ;; Fontify special declarations that lacks a type.
+      ;; Fontify special declarations that lack a type.
       ,@(when (c-lang-const c-typeless-decl-kwds)
 	  `((,(c-make-font-lock-search-function
 	       (concat "\\<\\("

lisp/progmodes/cc-langs.el

@@ -2588,6 +2588,7 @@ will be handled."
   ;; {...}").
   t    (append (c-lang-const c-class-decl-kwds)
 	       (c-lang-const c-brace-list-decl-kwds))
+  c nil
   ;; Note: "manages" for CORBA CIDL clashes with its presence on
   ;; `c-type-list-kwds' for IDL.
   idl  (append (c-lang-const c-typeless-decl-kwds)