Use rx for `gnu' compile.el pattern

* progmodes/compile.el (compilation-error-regexp-alist-alist):
Port `gnu' pattern to rx.

diff --cc lisp/ChangeLog
index 59f41b0,8ec39dc..bdf4e46
--- 1/lisp/ChangeLog
--- 2/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@@ -1,10 -1,8 +1,15 @@@
+ 2014-05-05  Daniel Colascione  <dancol@dancol.org>
+ 
+       * progmodes/compile.el (compilation-error-regexp-alist-alist):
+       Port `gnu' pattern to rx.
+ 
 +2014-05-05  Jarek Czekalski  <jarekczek@poczta.onet.pl>
 +
 +      Remove unneeded prompt when closing a buffer with active
 +      emacsclient ("Buffer ... still has clients"), #16548.
 +      * server.el (server-start): Remove the only call to:
 +      (server-kill-buffer-query-function): Remove.
 +
  2014-05-04  Leo Liu  <sdl.web@gmail.com>
  
        * calendar/diary-lib.el (calendar-chinese-month-name-array):