omap: Add CONFIG_SPL_VERIFY_IMAGE support This flag turns on image verification (crc in header and data). It'll only work if the u-boot.img file is used since it requires the header to do the verification. It also adds support for an alternate MMC location to find a second copy of the bootloader if the first one fails to verify. Change-Id: Ibfdbfd91dea0c725d9ce9d081e3004833a91ba47 Signed-off-by: Mike J. Chen <[email protected]>