misc: Added missing optional dependencies to 18.04 Docker

Change-Id: Ibc43664f99ce9fbd28d14352243fb17b7754289b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28892
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed