[ODE] Windows mingw compile problems

[Daniel Moser Tralamazza]

> Cool!  But how much does it help ODE overall?  Do you get even a 10% 
> speedup?
> 
> - Martin

don't know (yet). I can't run pure test_ode because I must compile using SINGLE,
so it fails when executed. I will make some "test_ode" like apps to see the
difference.

just to correct my previous post:
> testRecipSqrt(3.141592f)
> (simd) v=0.564190 [15263] (3.48x faster)
> (std)  v=0.564190 [53262]
>
> testSqrt(3.141592f)
> (simd) v=1.772454 [17053] (1.88x faster)
> (std)  v=1.772454 [32105]

What I have implemented so far: dSqrt, dRecipSqrt, dNormalize3/4, dDOT3/4,
dDOTgeneric(any size), dMatrix4MultiplyVector4().


Daniel