imx: imx8mq: build flash.bin

Build flash.bin for i.MX8MQ, it will include signed hdmi firmware,
spl, ddr firmware, fit image(bl31.bin, u-boot-nodtb.bin, dtb).
Burn it to 33KB offset of SD card.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
3 files changed