board/radxa/rock5b: use PARTLABEL to specify rootfs
This board has an optional eMMC module.
Use PARTLABEL to specify the rootfs, as this works regardless of the mmc
device probe order.
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Niklas Cassel