arm64: dts: rockchip: Enable sdio0 and uart0 on rk3399-roc-pc-mezzanine

The mezzanine board carries an E key type M.2 slot. This is
connected to USB, SDIO and UART0. Enable sdio and uart0 for use
with wlan and/or bt M.2 cards.

Signed-off-by: Markus Reichl <m.reichl@fivetechno.de>
Link: https://lore.kernel.org/r/20200109154211.1530-1-m.reichl@fivetechno.de


Signed-off-by: Heiko Stuebner <heiko@sntech.de>