devices-tile: only show specific types of mounts
devices-tile: only show specific types of mounts

Do not show shadowed mounts. Do not show mounts on non-removable
drives.

Fixes: #1060 PTP camera (canon ixus 30) shows twice in devices panel

meego-netbook-ux/meego-panel-devices,meego-netbook-ux/meego-panel-devices,meego-netbook-ux/meego-panel-devices