Add driver for the Renesas RCar PCIe controller present on Gen3 SoCs.
The PCIe on Gen3 is used both to connect external PCIe peripherals.
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>