imx8mq-u-boot: Pass FIT offset to fix boot regression

Since commit 37e50627 ("ARM: dts: imx: Convert i.MX8M flash.bin
image generation to binman") the imx8mq-evk fails to boot:

U-Boot SPL 2024.10-rc4 (Sep 09 2024 - 16:08:22 -0300)
PMIC:  PFUZE100 ID=0x10
SEC0:  RNG instantiated
Normal Boot
Trying to boot from MMC2

Fix it by passing the offset property for the FIT image, just like
it is done on i.MX8MM.

Fixes: 37e50627 ("ARM: dts: imx: Convert i.MX8M flash.bin image generation to binman")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Marek Vasut <marex@denx.de>