Properly quote symbols in documentation strings

Author: monnier

lisp/php-mode.el

@@ -943,8 +943,8 @@ This is was done due to the problem reported here:
 (defun php-lineup-string-cont (langelem)
   "Line up string toward equal sign or dot.
 e.g.
-$str \= \'some\'
-     . \'string\';
+$str = \\='some'
+     . \\='string';
 this ^ lineup"
   (save-excursion
     (goto-char (cdr langelem))