The whole RADEON_PACKAGES affair was introduced to deal
with fglrx/radeon incompatibility; it got basically
deprecated following fglrx removal from sisyphus,
and lakostis@ should have done "add" logic instead
of reusing the "set" one inappropriately.

Fixes: 85c52d71
See-also: https://lists.altlinux.org/pipermail/devel/2019-July/208126.html