hw/sd: ssi-sd: Support single block write

hw/sd: ssi-sd: Support single block write

Add 2 more states for the block write operation. The SPI host needs
to send a data start token to start the transfer, and the data block
written to the card will be acknowledged by a data response token.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
[PMD: Change VMState version id 6 -> 7]
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210128063035.15674-6-bmeng.cn@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>