[PATCH 1/2] Add support for the ar8316 switch.

This patch enhances the ar8216 driver with ar8316 support and fixes some minor
issues with the ar8216 driver itself. It should not break anything, but isn't
tested on ar8216 devices.

[PATCH 2/2] ar71xx: Add the ar8316 driver to rs pro/rb-450g.
Add the ar8216 driver to the ar71xx target, and add network
configurations for the RouterStation Pro and the RouterBoard RB-450G.

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@20722 3c298f89-4303-0410-b956-a3cf2f4a3e73