Update comment stating that it's fine to have a NULL GduDevice
Update comment stating that it's fine to have a NULL GduDevice

Signed-off-by: David Zeuthen <16a4bae6a7afea1fdd75baca6404fe68f285db96@redhat.com>
halfline/gvfs,xkahn/gvfs-cmis,philipl/gvfs,halfline/gvfs,cpatulea/gvfs,philipl/gvfs,cpatulea/gvfs,gicmo/gvfs,philipl/gvfs,gicmo/gvfs,gicmo/gvfs,xkahn/gvfs-cmis,halfline/gvfs,xkahn/gvfs-cmis,gicmo/gvfs,xkahn/gvfs-cmis