As far as I can tell, there are no Vulkan or openCL driver installed by
default, even if you have supported hardware. ANV, RADV and Beignet are in the
repos but are in the repos, but are not installed, and ROCM and Neo are not
even available in the repos. Instead, the needed drivers should be pulled in
automatically, so openCL and Vulkan is available out of the box if possible.
This would be RADV on Radeon, ANV on Intel, ROCM on supported Radeon setups,
Beignet on Ivy Bridge/Haswell, and Neo on Broadwell+.