* Broadcom cable/DSL/settop platforms

Required properties:

- compatible: "brcm,bcm3368", "brcm,bcm3384", "brcm,bcm33843"
              "brcm,bcm3384-viper", "brcm,bcm33843-viper"
              "brcm,bcm6328", "brcm,bcm6358", "brcm,bcm6362", "brcm,bcm6368",
              "brcm,bcm63168", "brcm,bcm63268",
              "brcm,bcm7125", "brcm,bcm7346", "brcm,bcm7358", "brcm,bcm7360",
              "brcm,bcm7362", "brcm,bcm7420", "brcm,bcm7425"

The experimental -viper variants are for running Linux on the 3384's
BMIPS4355 cable modem CPU instead of the BMIPS5000 application processor.
