FileDevice: implement icon ioctls

Fixes #9320.
usb_disk, usb_floppy: missing const.
Screen prefs: move driver info to main window

* Fixes relevant part of #5125
* The remaining information (serial number, frequency ranges) is
"advanced" and can be hidden in the tooltip. However, the video driver
used may be important important information, if you want to know if you
are using VESA, or if you have multiple video cards (Optimus for
example).
Screen prefs: force weight of the two boxes

Depending on the locale and string length the layout could leave only a
small part of the window for the rightmost part, which is the important
thing. Force the weight of each side so we have a more balanced window.