imx: fix get_boot_device() for imx8

commit 787f04bb6a0a ("imx: add USB2_BOOT type") broke get_boot_device()
for IMX8 which affects booting from SDP due to boot_instance being
non-zero.

Fix this by only using boot_instance for imx8ulp and imx9.

Fixes: 787f04bb6a0a ("imx: add USB2_BOOT type")
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Fabio Estevam <festevam@denx.de>
1 file changed