compiler: Add support for IBM Spectrum MPI

[JDBetteridge]

Obviously we cannot test this on CI, the MPI tests are currently running on an IBM machine to verify things are working

[codecov]

Codecov Report

❌ Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.39%. Comparing base (8209107) to head (5faf1d8).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
devito/arch/compiler.py	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2907      +/-   ##
==========================================
- Coverage   83.40%   83.39%   -0.02%     
==========================================
  Files         248      248              
  Lines       51633    51635       +2     
  Branches     4457     4458       +1     
==========================================
- Hits        43066    43062       -4     
- Misses       7812     7817       +5     
- Partials      755      756       +1     

Flag	Coverage Δ
pytest-gpu-aomp-amdgpuX	68.69% <0.00%> (-0.01%)	⬇️
pytest-gpu-gcc-	78.02% <0.00%> (+<0.01%)	⬆️
pytest-gpu-icx-	77.63% <0.00%> (-0.01%)	⬇️
pytest-gpu-nvc-nvidiaX	69.21% <0.00%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[JDBetteridge]

Okay, only one test failing on the IBM, but the same test fails locally for me. I don't think it should hold up merging this PR