gitlab-ci: Build radeonsi & RADV in the ppc64el job

This requires cross-building libdrm for ppc64el.

Reviewed-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3643>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3643>
2 files changed