Improve has_realtime_kernel method

[saikishor]

These changes allow the detection of realtime kernel even from the uname output. It should be more robust.

Fixes: #257

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 7 lines in your changes missing coverage. Please review.

Project coverage is 70.72%. Comparing base (1d66fed) to head (c0c3c60).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
src/realtime_helpers.cpp	0.00%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #260      +/-   ##
==========================================
- Coverage   71.67%   70.72%   -0.96%     
==========================================
  Files           9        9              
  Lines         519      526       +7     
  Branches       85       87       +2     
==========================================
  Hits          372      372              
- Misses         92       99       +7     
  Partials       55       55              

Flag	Coverage Δ
unittests	70.72% <0.00%> (-0.96%)	⬇️

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

Files with missing lines	Coverage Δ
src/realtime_helpers.cpp	37.14% <0.00%> (-2.66%)	⬇️

[alexswerner]

I think the approach is OK, but one thought:

• using #if !defined(_WIN32) on a feature which is Linux specific might be the wrong test

Hopefully the kernel uname output will always include this.

[saikishor]

@alexswerner yes! I had to do that to make the Windows CI work. If not, it doesn't compile at all. Maybe, I can fix it differently

[saikishor]

@alexswerner done!

[destogl]

Very good!