phy: rockchip-typec: use correct format for structure description

We get warning with W=1 build:
drivers/phy/rockchip/phy-rockchip-typec.c:360: warning: cannot
understand function prototype: 'struct rockchip_usb3phy_port_cfg '

The 'struct rockchip_usb3phy_port_cfg ' is commented properly but uses
wrong format, so fix that up

Link: https://lore.kernel.org/r/20200708132809.265967-4-vkoul@kernel.org


Signed-off-by: Vinod Koul <vkoul@kernel.org>