HID: hid-steam: Fix use-after-free when detaching device

When a hid-steam device is removed it must clean up the client_hdev used for
intercepting hidraw access. This can lead to scheduling deferred work to
reattach the input device. Though the cleanup cancels the deferred work, this
was done before the client_hdev itself is cleaned up, so it gets rescheduled.
This patch fixes the ordering to make sure the deferred work is properly
canceled.

Reported-by:  <syzbot+0154da2d403396b2bd59@syzkaller.appspotmail.com>
Fixes: 79504249 ("HID: hid-steam: Move hidraw input (un)registering to work")
Signed-off-by: Vicki Pfau <vi@endrift.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>