libx86 has been removed from openSUSE:Backports:SLE-15-SP7, but this introduced an issue with read-edid. Because read-edid BuildRequires: libx86-devel, it was no longer possible to build read-edid. This was fixed by updating openSUSE:Backports:SLE-15-SP/read-edid to the Factory version, which no longer needs libx86 to build. See https://build.opensuse.org/request/show/1202890