rpi: Add mmc 1 as a boot target

When booting with the rpi-firmware "mmc" overlay that disable
the SDHOST controller and use the SDHCI one for the sd card,
mmc 1 because a viable boot target.
Add it to the list

Signed-off-by: Oleksandr Tymoshenko <gonzo@FreeBSD.org>
Signed-off-by: Emmanuel Vadot <manu@freebsd.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
1 file changed