Disable TLS support on x86_64 explicitly.

* Building gcc-4.8.3 on x86_64 with TLS support fails with an internal
  compiler error. Until that problem is fixed, don't use TLS on x86_64,
  which (due to libstdc++ compatibility) requires the same for the
  host cross compiler.
Bump revision for gcc.
Merge branch 'master' into bootstrap-test