Now that all of the on-chip switch and basic platform support is updated,
we can now add all the hardware bits for the DB120.

* arge0/argemdio0 is hooked up to an AR8327 switch - which there's currently
  no support for.  However, the bootloader on this board does set it up as
  a basic switch so we can at least _use_ it ourselves.

  So we should at least configure the arge0 side of things, including the GMAC
  register.

* .. the GMAC config peels off arge0 from the internal switch and exposes it
  as an RGMII to said AR8327.

* arge1/argemdio1 are hooked up to an internal 10/100 switch.  So, that also
  needs configuring.

* Add support for the NOR flash layout.

* Add support for the wifi (which works, with bugs, but it works.)

What's missing!

* No GPIO stuff yet!
* No sound (I2S) and no NAND flash support yet, sorry!
* The normal DB120 has an external AR95xx wifi chip on PCIe but with the
  actual calibration data in the NOR flash.  My DB120 has been modified
  to let me use the PCIe slot as a normal PCIe slot.  I'll add the "default"
  settings later when I have access to a non-modified one.
* Other stuff, like why the wifi unit gets upset and spits out stuck beacons
  and interrupt storms everywhere.  Sigh.

Tested:

* DB120 board - AR9344 (mips74k SoC) booting off of SPI flash into multi-user
  mode.
Rename Free() macro to R_Free(). This matches R_Malloc() and has much lower
probability to clash with other headers.

Submitted by:	Eric van Gyzen <eric_van_gyzen dell.com>
For VIMAGE kernels store vnet in the struct task, and set vnet context
during task processing.

Reported & tested by:	mm