PCI: xilinx: Allow build on MIPS platforms

Allow the xilinx-pcie driver to be built on MIPS platforms which make use
of generic PCI drivers rather than legacy MIPS-specific interfaces.  This
is used on the MIPS Boston development board.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Bharat Kumar Gogada <bharatku@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Ravikiran Gummaluri <rgummal@xilinx.com>

drivers/pci/host/Kconfig

@@ -71,7 +71,7 @@ config PCI_HOST_GENERIC
 
 config PCIE_XILINX
 	bool "Xilinx AXI PCIe host bridge support"
-	depends on ARCH_ZYNQ || MICROBLAZE
+	depends on ARCH_ZYNQ || MICROBLAZE || (MIPS && PCI_DRIVERS_GENERIC)
 	help
 	  Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
 	  Host Bridge driver.