GitLab service scheduled maintenance on Tuesday, March 26th 2024 as of 17h30 Geneva time for a period of 6 hours. Further information under https://cern.ch/otg0148934.
Various places in LHCbMath and the RICH were declaring a simple AVX 'guard' class that calls
_mm256_zeroupper() when it goes out of scope. This MR simply makes a public header for this class which all users can then share.