uboot-imx

MLK-17200-1 mx7ulp: Add CPU revision check for B0

Since there is no register for CPU revision, we use ROM version to
check the A0 or B0 chip.

Signed-off-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
(cherry picked from commit 9ad30c8439ece3a8b88040847155405fca40facf)
(cherry picked from commit 380791dc105256494d30fc1883978808cf83fc04)