org-list: Fix "Stack overflow in regexp matcher"

* lisp/org-list.el (org-list-item-body-column): Do not backtrack as
  much in regexp.

Reported-by: Vasilij Schneidermann <v.schneidermann@gmail.com>
<http://permalink.gmane.org/gmane.emacs.orgmode/110885>

lisp/org-list.el

@@ -2097,11 +2097,13 @@ Possible values are: `folded', `children' or `subtree'.  See
   "Return column at which body of ITEM should start."
   (save-excursion
     (goto-char item)
-    (looking-at "[ \t]*\\(\\S-+\\)\\(.*[ \t]+::\\)?\\([ \t]+\\|$\\)")
+    (looking-at "[ \t]*\\(\\S-+\\)\\(.*[ \t]::\\)?\\([ \t]\\|$\\)")
     (if (match-beginning 2)
 	(let ((start (1+ (match-end 2)))
 	      (ind (org-get-indentation)))
-	  (if (> start (+ ind org-list-description-max-indent)) (+ ind 5) start))
+	  (if (> start (+ ind org-list-description-max-indent))
+	      (+ ind 5)
+	    start))
       (+ (progn (goto-char (match-end 1)) (current-column))
 	 (if (and org-list-two-spaces-after-bullet-regexp
 		  (string-match-p org-list-two-spaces-after-bullet-regexp