pci: kconfig: Setup proper dependency for PCIE_ROCKCHIP

There is missing dependency for PCIE_ROCKCHIP which selects
PHY_ROCKCHIP_PCIE which directly depends on ARCH_ROCKCHIP.

WARNING: unmet direct dependencies detected for PHY_ROCKCHIP_PCIE
  Depends on [n]: ARCH_ROCKCHIP [=n]
  Selected by [y]:
  - PCIE_ROCKCHIP [=y] && PCI [=y]

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Tom Rini <trini@konsulko.com>