riscv: dts: starfive: Enable PCIe host controller

Enable and add pinctrl configuration for PCIe host controller.

Signed-off-by: Mason Huo <mason.huo@starfivetech.com>
Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>