Proposed changes

Microsoft MPI Redist and SDK installers set environment variables (MSMPI_BIN, MSMPI_INC, MSMPI_LIB32, MSMPI_LIB64) that described in the example in Microsoft MPI repository. These environment variables are widely used. For example, CMake uses them in it's FindMPI module there and there, Meson also uses these variables to locate MS-MPI.

This PR changes the way MS-MPI is searched. Instead of hardcoded paths to MS-MPI Redist and SDK, paths from environment variables mentioned above are used. This allows to use MS-MPI Redist and SDK installed to custom path.

I tested these changes with the latest MS-MPI Redist and SDK installed to the default path and to custom path.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Documentation content changes
• Other (please describe):

Checklist

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• I searched the discussions
• I searched the closed and open issues
• I read the contribution guidelines
• I added myself to the copyright attributions for significant changes
• I checked that tests pass locally with my changes
• I added tests that prove my fix is effective or that my feature works
• I added necessary documentation (if appropriate)