Delete defgroup "wp" obsolete since Emacs 26

* lisp/cus-edit.el (wp): Delete defgroup obsolete since Emacs 26.
(text): Don't inherit obsolete customization group 'wp'.
* lisp/finder.el (finder-known-keywords): Delete 'wp' keyword.

etc/NEWS

@@ -167,6 +167,9 @@ A new ':authorizable t' parameter has been added to 'dbus-call-method'
 and 'dbus-call-method-asynchronously' to allow the user to interactively
 authorize the invoked D-Bus method (e.g., via polkit).
 
+** The customization group 'wp' has been removed.
+It has been obsolete since Emacs 26.1.  Use the group 'text' instead.
+
 
 * Changes in Emacs 31.1 on Non-Free Operating Systems
 

lisp/cus-edit.el

@@ -175,16 +175,9 @@
   "Support for editing files."
   :group 'emacs)
 
-(defgroup wp nil
-  "Support for editing text files.
-Use group `text' for this instead.  This group is obsolete."
-  :group 'emacs)
-
 (defgroup text nil
   "Support for editing text files."
-  :group 'emacs
-  ;; Inherit from deprecated `wp' for compatibility, for now.
-  :group 'wp)
+  :group 'emacs)
 
 (defgroup data nil
   "Support for editing binary data files."

lisp/finder.el

@@ -71,8 +71,7 @@
     (text	. "editing text files")
     (tools	. "programming tools")
     (unix	. "UNIX feature interfaces and emulators")
-    (vc		. "version control")
-    (wp		. "use keyword `text' instead; this keyword is obsolete"))
+    (vc		. "version control"))
   "Association list of the standard \"Keywords:\" headers.
 Each element has the form (KEYWORD . DESCRIPTION).")