bug#37500: [PATCH] Change quotes referencing `calc-mode' to standard syntax

[Noah Swainland <nks@nks.sh>]

When reading `C-h f calc`, it is stated that full documentation is
listed under "calc-mode".  The use of double quotation marks means
that the user then has to search manually for the calc-mode
documentation.  By using the standard grave accent and apostrophe, the
reference is displayed as a link.
---
 lisp/calc/calc.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/calc/calc.el b/lisp/calc/calc.el
index 8e76296273..ad483b406d 100644
--- a/lisp/calc/calc.el
+++ b/lisp/calc/calc.el
@@ -1394,7 +1394,7 @@ commands given here will actually operate on the *Calculator* stack."
 
 ;;;###autoload
 (defun calc (&optional arg full-display interactive)
-  "The Emacs Calculator.  Full documentation is listed under \"calc-mode\"."
+  "The Emacs Calculator.  Full documentation is listed under `calc-mode'."
   (interactive "P\ni\np")
   (if arg
       (unless (eq arg 0)
-- 
2.20.1