We read from the cdb[] buffer in ata_exec_internal_sg().  It has to be
ATAPI_CDB_LEN (16) bytes long, but this buffer is only 12 bytes.

Fixes: 21334205 ("libata: handle power transition of ODD")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org