ide: missing break statement in set_timings_mdma()

There was clearly supposed to be a break statement here.  Currently we
use the k2 ata timings instead of sh ata ones we intended.  Probably no
one has this hardware anymore so it likely doesn't make a difference
beyond the static checker warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>