AMDGPU+RadeonSI Is Much Faster Than The Old Proprietary Fglrx Driver

With going back to test Ubuntu 14.04 through Ubuntu 17.10's Radeon OpenGL performance as part of marking AMD's open-source strategy turning a decade old, I also took this opportunity while having an old Ubuntu installation running to also re-test the former Catalyst/fglrx driver stack that's since been succeeded by AMDGPU-PRO and AMDGPU+RadeonSI.