[v3] fix darwin FAIL in 30_threads/thread/native_handle/typesizes.cc

[Jonathan Wakely]

        * testsuite/30_threads/thread/native_handle/typesizes.cc: Do not run
        on darwin.

This fixes a FAIL on darwin:
http://gcc.gnu.org/ml/gcc-testresults/2011-11/msg01606.html

It passes (by design) on GNU/Linux but there's no reason to assume or
require that this test passes elsewhere.

Index: testsuite/30_threads/thread/native_handle/typesizes.cc
===================================================================
--- testsuite/30_threads/thread/native_handle/typesizes.cc      (revision 
181459)
+++ testsuite/30_threads/thread/native_handle/typesizes.cc      (working copy)
@@ -1,7 +1,7 @@
-// { dg-do run { target *-*-linux* *-*-solaris* *-*-cygwin *-*-darwin* 
alpha*-*-osf* mips-sgi-irix6* } }
+// { dg-do run { target *-*-linux* *-*-solaris* *-*-cygwin alpha*-*-osf* 
mips-sgi-irix6* } }
 // { dg-options " -std=gnu++0x -pthread" { target *-*-linux* alpha*-*-osf* 
mips-sgi-irix6* } }
 // { dg-options " -std=gnu++0x -pthreads" { target *-*-solaris* } }
-// { dg-options " -std=gnu++0x " { target *-*-cygwin *-*-darwin* } }
+// { dg-options " -std=gnu++0x " { target *-*-cygwin } }
 // { dg-require-cstdint "" }
 // { dg-require-gthreads "" }