[PATCH v2] MIPS: NI 169445 board support

[Nathan Sullivan]

This adds support for the National Instruments 169445 MIPS system.

----

Changes from v1:

- Add GPIO patch and board support patch to one set
- Address Rob Herring's device tree feedback
- Convert the 169445 to a generic MIPS board
- Switch to the newer stmmac driver for the board's ethernet core