Add driver for the Socionext UniPhier Pro5 SoC endpoint controller.
This controller is based on the DesignWare PCIe core.

And add "host" to existing controller descriontions for the host controller
in Kconfig.

Link: https://lore.kernel.org/r/1589457801-12796-3-git-send-email-hayashi.kunihiko@socionext.comSigned-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>