all float3 and float4 functions and isas

completed all options of float3 and float4 functions in isas and math_c
neon still to be done but that will be on mac.

Engine/source/math/public/float3_dispatch.h

@@ -21,6 +21,7 @@ namespace math_backend::float3::dispatch
       void (*normalize)(float*) = nullptr;
       void (*normalize_mag)(float*, float) = nullptr;
       void (*lerp)(const float*, const float*, float, float*) = nullptr;
+      void (*cross)(const float*, const float*, float*) = nullptr;
    };
 
    // Global dispatch table