Add linux-pam into g-b-m after removed from freedesktop-sdk
Looks like https://gnome1.codethink.co.uk/logs/build-2019-07-29-091101/build-gnome-apps-nightly-master-org.gnome.Builder-aarch64.txt is breaking as result of the removal
Looks like https://gnome1.codethink.co.uk/logs/build-2019-07-29-091101/build-gnome-apps-nightly-master-org.gnome.Builder-aarch64.txt is breaking as result of the removal