hw/block/nvme: reject io commands if only admin command set selected

hw/block/nvme: reject io commands if only admin command set selected

If the host sets CC.CSS to 111b, all commands submitted to I/O queues
should be completed with status Invalid Command Opcode.

Note that this is technically a v1.4 feature, but it does not hurt to
implement before we finally bump the reported version implemented.

Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>