auto-tester breakage

[Brad Roberts]

I noticed that the GDC auto-tester failed the most recent build cycle.  I assumed it was due to 
having an old snapshot.  After updating it, the build failed in the same way.

The 'old' snapshot:  GCC_VER=4.9-20130929
The one it's running now:  GCC_VER=4.9-20131117

The errors:

In file included from ../../gcc-4.9-20131117/gcc/d/d-lang.cc:22:0:
../../gcc-4.9-20131117/gcc/d/d-system.h:42:21: fatal error: attribs.h: No such file or directory
  #include "attribs.h"
                      ^
compilation terminated.
In file included from ../../gcc-4.9-20131117/gcc/d/d-decls.cc:19:0:
../../gcc-4.9-20131117/gcc/d/d-system.h:42:21: fatal error: attribs.h: No such file or directory
  #include "attribs.h"
                      ^
compilation terminated.