PSA: Ubuntu 20.04 drivers require render group access

[tchiers]

I imagine a bunch of people will be upgrading to Ubuntu 20.04 now that the pointrelease has been made - hope my evening spent dicking around with this can save you a bit of time.

A change in the amdgpu install now requires your fahclient user to have render group in order to access the hardware and fold on GPU - previously it just needed video. This is not something either do-release-upgrade or new amdgpu install will handle, so you must do it on your own.

[bruce]

I created a placeholder ticket for this enhancement. If you have github access, please add details there.
https://github.com/FoldingAtHome/fah-issues/issues/1548

[tchiers]

Done.