rockchip: rk3399-roc-pc: default to SPI bus 1 for SPI-flash

SPI flash on this board is located on bus 1, default to using bus 1 for
SPI flash on both rk3399-roc-pc and -mezzanine, and stop aliasing it to
bus 0.

Signed-off-by: Hugh Cole-Baker <sigmaris@gmail.com>
Suggested-by: Simon Glass <sjg@chromium.org>
Fixes: c4cea2bb ("rockchip: Enable building a SPI ROM image on bob")
Reviewed-by: Kever <Yang&lt;kever.yang@rock-chips.com>