Sync toplevel files with GCC

Sync toplevel files with GCC

2012-11-13  Richard Henderson  <rth@redhat.com>

	* configure.ac: Move libsanitizer logic to subdirectory.
	* configure: Regenerate.

2012-11-13  Dodji Seketeli  <dodji@redhat.com>

	* configure.ac: Enable libsanitizer just on x86 linux for now.
	* configure: Re-generate.

2012-11-13  David Edelsohn  <dje.gcc@gmail.com>

	* configure.ac: Merge libquadmath sections.
	* configure: Regenerate.

2012-11-12  Wei Mi <wmi@google.com>

	* configure.ac: Add libsanitizer to target_libraries.
	* Makefile.def: Ditto.
	* configure: Regenerate.
	* Makefile.in: Regenerate.