Do not go beyond ARRAY_SIZE of tape_device and viotape_unitinfo
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Acked-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>