AVX2 acceleration is only compiling with MSVC build system

[RedNicStone]

When just using the main header file morton.h the preprocessor directives disallow compilation of AVX2 accelerated functions when using any compiler other than MSVC. See these lines:

#if defined(__BMI2__) || (defined(__AVX2__) && defined(_MSC_VER))
#include "morton_BMI.h"
#elif defined(__AVX512BITALG__)
#include "morton_AVX512BITALG.h"
#endif

I don't see any apparent reason for this but the effect is that building is prevented on most compiler systems.
I would appreciate removal of this requirement if it isn't there on purpose as my current solution is a duplicated morton.h without the directives which is neither beautiful nor a good solution.

Thanks for your support!

[Forceflow]

Good call, will fix