Resolve updated codecheck issues

[adlarkin]

This PR is meant to resolve new codecheck issues introduced by gazebosim/gz-cmake#117.

From my understanding, the plan is to forward port the fixes here to all other ignition versions once gazebosim/gz-cmake#117 is merged.

Signed-off-by: Ashton Larkin [email protected]

[codecov]

Codecov Report

Merging #175 into ign-math6 will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           ign-math6     #175   +/-   ##
==========================================
  Coverage      99.22%   99.22%           
==========================================
  Files             59       59           
  Lines           5920     5920           
==========================================
  Hits            5874     5874           
  Misses            46       46           

Impacted Files	Coverage Δ
src/Kmeans.cc	100.00% <100.00%> (ø)

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[adlarkin]

I had to add // NOLINT to the do ... while loop in order to resolve a false positive from the new cpplint (it thought this was an empty loop):

https://github.com/ignitionrobotics/ign-math/blob/ec665461f4f9a557e00f0a912b0a4d56800f095e/src/Kmeans.cc#L152