Cleanup some HRTF code
Cleanup some HRTF code

Use loops instead of duplicating code, rewrite some lines to be clearer.

irungentoo/openal-soft-tox,irungentoo/openal-soft-tox,arkana-fts/openal-soft,alexxvk/openal-soft,Wemersive/openal-soft,arkana-fts/openal-soft,alexxvk/openal-soft,BeamNG/openal-soft,aaronmjacobs/openal-soft,BeamNG/openal-soft,aaronmjacobs/openal-soft,Wemersive/openal-soft