uboot-imx

drivers: spi: consider command bytes when sending transfers

Command bytes are part of the written bytes and they should be taken into
account when sending a spi transfer.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>