There is a slab-out-of-bounds Write bug in hid-bigbenff driver.
The problem is the driver assumes the device must have an input but
some malicious devices violate this assumption.

Fix this by checking hid_device's input is non-empty before its usage.
Reported-by: Nsyzkaller <syzkaller@googlegroups.com>
Signed-off-by: NDongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>