MIPS: pci: convert lantiq driver to OF

Implement support for OF inside the lantiq PCI driver. The patch also splits
pcibios_plat_dev_init and pcibios_map_irq out into their own file to accomodate
coexistance with the upcoming pcie driver.

Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3806/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/lantiq/Kconfig b/arch/mips/lantiq/Kconfig
index 9485fe5..7389098 100644
--- a/arch/mips/lantiq/Kconfig
+++ b/arch/mips/lantiq/Kconfig
@@ -18,7 +18,6 @@
 	select HW_HAS_PCI
 endchoice
 
-
 choice
 	prompt "Devicetree"
 
@@ -27,4 +26,8 @@
 	depends on SOC_XWAY
 endchoice
 
+config PCI_LANTIQ
+	bool "PCI Support"
+	depends on SOC_XWAY && PCI
+
 endif