Re-add the regulator-always-on property for vcc_sdio which supplies sdmmc,
since it gets disabled during reboot now and the bootrom expects it to be
enabled  when booting from SD card. This makes rebooting impossible in that
case and requires a hard reset to boot again.

Fixes: 04a0077f ("arm64: dts: rockchip: Remove always-on properties from regulator nodes on rk3399-roc-pc.")
Signed-off-by: Alex Bee <knaerzche@gmail.com>
Link: https://lore.kernel.org/r/20210619121306.7740-1-knaerzche@gmail.comSigned-off-by: Heiko Stuebner <heiko@sntech.de>