Add AR9340 switch support to the build.
Fix the Wii build, and remove an extraneous critical_enter().
Add support for the AR9340 switch to the switch framework.

* Do the hardware setup in the right order!
* Modify/improve the chip probe check so it can actually
  probe the 7240/9340 directly (although it's not yet used..)
* Initialise and fetch the is_mii option
* Fix some debugging whilst I'm here.

This is enough to get things off the ground.

Tested:

* AR9344 SoC
Add a big, big note to the vlan code that it needs to be taught
about the new VLAN options for the AR9340 and AR8327 chips.
Yes, this board has 128mb of RAM.