Provide a couple of fixes for XL on power9

[KineticTheory]

Background

• Allows CI to run on Darwin Power9 for XL.

Purpose of Pull Request

• Relates to re-git issue 26

Status

• Reference:
  • Pre-Merge Code Review
  • CDash Status
• Checks
  • Travis/Appveyor CI checks pass
  • Code coverage does not decrease
  • Valgrind test passes
  • Toss3 checks pass
  • Trinitite checks pass
  • Code reviewed/approved, sufficient DbC checks, testing, documentation

[codecov]

Codecov Report

Merging #1108 (7e1951d) into develop (a659254) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           develop   #1108   +/-   ##
=======================================
  Coverage     88.7%   88.7%           
=======================================
  Files          374     374           
  Lines        18593   18593           
=======================================
  Hits         16497   16497           
  Misses        2096    2096