bmips: add support for Netgear EVG2000

bmips: add support for Netgear EVG2000

The Netgear EVG2000 is a wifi gigabit router, 2.4 GHz single band with
two internal antennas integrated in the main PCB.

Hardware:
 - SoC: Broadcom BCM6369
 - CPU: dual core BMIPS4350 V3.1 @400Mhz
 - RAM: 64 MB DDR
 - Flash: 16 MB parallel NOR
 - LAN switch: Broadcom BCM53115, 5x 1Gbit
 - Wifi 2.4 GHz: Broadcom BCM4322 802.11bgn
 - USB: 2x 2.0
 - Buttons: 2x, 1 reset
 - LEDs: 10x
 - FXS: 2x
 - UART: yes

Installation via CFE web UI:
  1. Power off the router and make a temporal TX-RX shortcircuit on the
     serial pins.
  2. Power on the router and wait 3 or more seconds
  3. Remove the TX-RX shortcircuit
  4. Browse to http://192.168.1.1 or http://192.168.0.1 and upload the
     firmware
  5. Wait a few minutes for it to finish

Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com>