Patch for GNU sed version 4.2.1

The attached patch file will fix a 1 byte leak in sed version 4.2.1. The
file "sed-26428.valgrind" is Valgrind's output before I patched sed. The
other file is Valgrind's output after I patched sed.
The command line I used to find the leak was:
echo 'libreoffice -> soffice.bin' | valgrind --log-file=sed-%p.valgrind
--leak-check=full sed/sed 's/.*libreoffice -> //g'

--- sed/compile.c	2012/03/23 16:42:18	1.1
+++ sed/compile.c	2012/03/23 16:42:36
@@ -870,6 +870,7 @@
 
   tail->next = NULL;
   sub->replacement = root.next;
+  free(base);
 }
 
 static void read_text P_((struct text_buf *buf, int leadin_ch));