devel/libvirt: drop unused Meson options after e03306805502

meson.build:1:0: ERROR: Unknown options: "dbus, hal"

https://gitlab.com/libvirt/libvirt/-/commit/cf6cc86cd217
https://gitlab.com/libvirt/libvirt/-/commit/de3289e2b538

PR: 259080
Reported by: antoine (via exp-run)
Regressed by: https://github.com/mesonbuild/meson/commit/dbf2ace6ca1c