uboot-imx

sandbox: Introduce Kconfig option for 32/64 bit host

It seems most of the time we are building and running sandbox on 64-bit host.
But we do support 32-bit host as well. Introduce Kconfig option for this.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>