[ODE] Fix leaking of s_cachedPosR in collision_kernel.cpp

[Jason Perkins]

On 6/18/06, Jon Watte (ODE) <hplus-ode at mindcontrol.org> wrote:
> When using leak checking allocators, the cached posR
> inside collision_kernel.cpp gets reported. This patch
> makes sure it gets disposed before the Windows leak
> checker finds it, enabling a clean test run (at least
> in my test code).

This does the trick, but would it be better to do it in dCloseODE()?

Jason