The bit to see if a CD is valid is the last bit of the first word of the CD.

Signed-off-by: Joe Komlodi <joe.komlodi@xilinx.com>
Message-id: 1626728232-134665-2-git-send-email-joe.komlodi@xilinx.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>