Reworked the openrc init files.
Installs to /usr/$(get_libdir) now.
Avoids pointless copying for CUDA/ROCM files just to delete them afterwards.
Closes: https://bugs.gentoo.org/950633
Closes: https://bugs.gentoo.org/946268
Signed-off-by: Paul Zander <negril.nx+gentoo@gmail.com>