Debug Flag on AMD systems

MKL libraries are known to be hampered on AMD processors.
There appears to be a undocumented environment flag to improve on that, for now, as seen here:
https://www.pugetsystems.com/labs/hpc/How-To-Use-MKL-with-AMD-Ryzen-and-Threadripper-CPU-s-Effectively-for-Python-Numpy-And-Other-Applications-1637/

The VML documentation is
https://software.intel.com/en-us/mkl-macos-developer-guide-setting-the-default-mode-of-vector-math-with-an-environment-variable

I am currently lacking the time implement and the AMD system to test but putting here for reference.

No source file or test is named. Start by reviewing the linked Puget Systems article and Intel VML documentation, then inspect IntelVectorMath.jl for its environment-variable or initialization entry points. Done means the AMD-related flag behavior is implemented or clearly documented and verified on an AMD system.

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