Corrected version of gcc_bootstrap to match the version in HaikuPorts recipe.

* There was a version mismatch between HaikuPorts gcc_bootstrap recipe
  and build/jam/repositories/HaikuPortsCross/arm which prevented
  building @bootstrap-raw for ARM. Thanks Ingo for helping out!
* Ditto for ppc, x86, x86_64.

Signed-off-by: Jérôme Duval <jerome.duval@gmail.com>