ox: Remove `org-export-solidify-link-text'

* lisp/ox.el (org-export-solidify-link-text): Remove function.

* etc/ORG-NEWS: Signal removal.

etc/ORG-NEWS

@@ -103,6 +103,9 @@ it provides more features and covers all export back-ends.  It is also
 accessible from the export dispatcher.
 *** Removed function ~org-timer-cancel-timer~
 ~org-timer-stop~ now stops both relative and countdown timers.
+*** Removed function ~org-export-solidify-link-text~
+This function, being non-bijective, introduced bug in internal
+references.  Use ~org-export-get-reference~ instead.
 *** Removed function ~org-end-of-meta-data-and-drawers~
 The function is superseded by ~org-end-of-meta-data~, called with an
 optional argument.

lisp/ox.el

@@ -3896,9 +3896,6 @@ meant to be translated with `org-export-data' or alike."
 ;; `org-export-custom-protocol-maybe' handles custom protocol defined
 ;; with `org-add-link-type', which see.
 ;;
-;; `org-export-solidify-link-text' turns a string into a safer version
-;; for links, replacing most non-standard characters with hyphens.
-;;
 ;; `org-export-get-coderef-format' returns an appropriate format
 ;; string for coderefs.
 ;;
@@ -3917,11 +3914,6 @@ meant to be translated with `org-export-data' or alike."
 ;; number in the element it belongs, or returns the reference itself
 ;; when the element isn't numbered.
 
-(defun org-export-solidify-link-text (s)
-  "Take link text S and make a safe target out of it."
-  (save-match-data
-    (mapconcat 'identity (org-split-string s "[^a-zA-Z0-9_.-:]+") "-")))
-
 (defun org-export-custom-protocol-maybe (link desc backend)
   "Try exporting LINK with a dedicated function.