HID: hiddev: Add 32bit ioctl compatibilty

The hiddev driver currently lacks 32bit ioctl compatibility, so
if you're running with a 64bit kernel and 32bit userspace, it won't
work.

I'm pretty sure that the only thing missing is a compat_ioctl
implementation as all structs have fixed size fields.

With this change I can use revoco to configure my MX Revolution mouse.

Signed-off-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>