Add dts file for ROC-RK3308-CC from firefly.
Sync form linux rockchip for v5.5-armsoc/dts64:
"arm64: dts: rockchip: Add devicetree for board roc-rk3308-cc"
(sha1: 4403e1237be3af0977aa23ef399e3496316317a0)
Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>