[libitm] fix reentrant.c testcase

[Patrick Marlier]

In the reentrant.c testcase, the first transaction has no transactional 
access and thus removed.
In order to keep this transaction, I added a shared access inside.
Tested on i686.
OK to commit?
(I don't have an account, so thanks in advance to committer)
--
Patrick Marlier.
2012-01-04  Patrick Marlier  <patrick.marl...@gmail.com>

        * testsuite/libitm.c/reentrant.c: Adjust testcase.
Index: testsuite/libitm.c/reentrant.c
===================================================================
--- testsuite/libitm.c/reentrant.c	(revision 182883)
+++ testsuite/libitm.c/reentrant.c	(working copy)
@@ -1,4 +1,4 @@
-/* { dg-do run { xfail *-*-* } }
+/* { dg-do run }
 /* { dg-options "-pthread" } */
 
 /* Tests that new transactions can be started from both transaction_pure and
@@ -36,7 +36,7 @@ int __attribute__((transaction_unsafe)) unsafe(int
 static void *thread (void *dummy __attribute__((unused)))
 {
   __transaction_atomic {
-    pure(1);
+    pure(x);
   }
   __transaction_relaxed {
     unsafe(1);