arm: dts: rockchip: rk3399: nanopi-r4s: Provide smbios sysinfo

Provide human-readable manufacturer and product names for the
FriendlyELEC NanoPi R4S.

Enable CONFIG_SYSINFO and CONFIG_SYSINFO_SMBIOS by default.

Signed-off-by: Christian Kohlschütter <christian@kohlschutter.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>