It's a moving target that keeps breaking. Right now it's broken because
removing openssl-devel causes removal of dkms, which DIB insists on
installing.
Document the supported distributions based on what the CI runs
(yes, it's Ubuntu Bionic and openSUSE 15.1, there is no mistake).
Change-Id: I08263751ca158db5883d95407ad0f3c9807826eb