HID: hid-debug: Show rdesc for unclaimed devices

Since commit a7197c2e, the raw report descriptor is available also for
unclaimed devices. This patchs make it show in the rdesc debugfs node.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>