arm64: dts: renesas: spider-cpu: Enable eMMC0

This enables the on-board eMMC on the Spider board. Switch SW3 has to be
in the default (neutral) position. Other settings will not be supported
upstream!

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20220711134656.277730-4-wsa+renesas@sang-engineering.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>