MIPS: ralink: add rt2880 pci driver

Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/8034/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --cc arch/mips/pci/Makefile
Simple merge

diff --cc arch/mips/pci/pci-rt2880.c
Simple merge

diff --cc arch/mips/ralink/Kconfig
Simple merge