PCI: rockchip: Add Kconfig COMPILE_TEST

Allow selection of the Rockchip driver for compile testing, even if we
aren't building for ARCH_ROCKCHIP.

[bhelgaas: changelog]
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

drivers/pci/host/Kconfig

@@ -276,7 +276,7 @@ config PCIE_ARTPEC6
 
 config PCIE_ROCKCHIP
 	bool "Rockchip PCIe controller"
-	depends on ARCH_ROCKCHIP
+	depends on ARCH_ROCKCHIP || COMPILE_TEST
 	depends on OF
 	depends on PCI_MSI_IRQ_DOMAIN
 	select MFD_SYSCON