Haiku: fixed uninitialized variable.

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extra : rebase_source : c5f25703a87bb8090bfa567cd3af215901c15a69
Apparently Haiku is removing /boot/common (thanks, scottmc!).

 See http://lists.libsdl.org/pipermail/sdl-libsdl.org/2013-November/091877.html

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extra : rebase_source : ba62cd08f9b972bb14e1f7fbe350dd35e427743f