gio-tool-info: Print unix mount information where available
gio-tool-info: Print unix mount information where available

"gio info" output doesn't contain any information about mount points, but
that information can be useful when debugging issues in facilities that
depend on knowing about mount points, such as the trash API.

Signed-off-by: Simon McVittie <0e1aea601907c1a85c2dc96e5ea37e23c58d2e9b@collabora.com>
Co-authored-by: Ondrej Holy <79f5abba52d1903ec2619f9259574478b3551c8f@redhat.com>

endlessm/glib,endlessm/glib,endlessm/glib,endlessm/glib,endlessm/glib