ARM: Kirkwood: Update PCI-E fixup

- The code relies on rc_pci_fixup being called, which only happens
  when CONFIG_PCI_QUIRKS is enabled, so add that to Kconfig. Omitting
  this causes a booting failure with a non-obvious cause.
- Update rc_pci_fixup to set the class properly, copying the
  more modern style from other places
- Correct the rc_pci_fixup comment

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index ade7e92..9759fec 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -547,6 +547,7 @@
 	select CPU_FEROCEON
 	select GENERIC_CLOCKEVENTS
 	select PCI
+	select PCI_QUIRKS
 	select PLAT_ORION_LEGACY
 	help
 	  Support for the following Marvell Kirkwood series SoCs: