ci/lava: Don't build VK-main for arm64

Only amd64 needs the VK-main build, as it's only used by Raven and
Stoney on RADV.

Signed-off-by: Valentine Burley <valentine.burley@collabora.com>
Reviewed-by: Eric Engestrom <None>
Reviewed-by: Antonio Ospite <None>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33377>
1 file changed