Fix minor quoting problems in diagnostics

* lisp/tutorial.el (tutorial--describe-nonstandard-key):
* lisp/vc/ediff-ptch.el (ediff-fixup-patch-map):
Follow text-quoting-style in diagnostic, and quote a file name.

lisp/tutorial.el

@@ -135,7 +135,7 @@ options:
                            ;; then save this value in mapsym
                            (setq mapsym s)))))
             (insert
-             (format
+             (format-message
               "The default Emacs binding for the key %s is the command `%s'.  "
               (key-description key)
               db))

lisp/vc/ediff-ptch.el

@@ -333,7 +333,7 @@ program."
 		      (ediff-with-current-buffer standard-output
 			(fundamental-mode))
 		      (princ
-		       (format "
+		       (format-message "
 The patch file contains a context diff for
 	%s
 	%s
@@ -342,7 +342,7 @@ to be patched on your system.  If you know the correct file name,
 please enter it now.
 
 If you don't know and still would like to apply patches to
-other files, enter /dev/null
+other files, enter `/dev/null'.
 "
 			       (substring (car proposed-file-names) 6)
 			       (substring (cdr proposed-file-names) 6))))