bug#44611: Prefix arg for xref-goto-xref

[Juri Linkov]

I recall endless discussions about xref in the past.
But now I realized that xref-goto-xref just misses
an obvious thing, and nothing more is needed.

Like e.g. 'quit-window' allows using a prefix argument
to change its behavior by relying on (interactive "P"),
xref-goto-xref should do the same:

diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index a1c4c08c26..e1dd6e56bb 100644
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -600,9 +600,9 @@ xref--item-at-point
 
 (defun xref-goto-xref (&optional quit)
   "Jump to the xref on the current line and select its window.
-Non-interactively, non-nil QUIT means to first quit the *xref*
-buffer."
-  (interactive)
+Non-interactively, non-nil QUIT, or interactively, with prefix argument
+means to first quit the *xref* buffer."
+  (interactive "P")
   (let* ((buffer (current-buffer))
          (xref (or (xref--item-at-point)
                    (user-error "No reference at point")))