arch/tile: tilegx PCI root complex support

This change implements PCIe root complex support for tilegx using
the kernel support layer for accessing the TRIO hardware shim.

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> [changes in 07487f3]
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 645979c..a5302d3 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -356,6 +356,9 @@
 	default y
 	select PCI_DOMAINS
 	select GENERIC_PCI_IOMAP
+	select TILE_GXIO_TRIO if TILEGX
+	select ARCH_SUPPORTS_MSI if TILEGX
+	select PCI_MSI if TILEGX
 	---help---
 	  Enable PCI root complex support, so PCIe endpoint devices can
 	  be attached to the Tile chip.  Many, but not all, PCI devices