beaglebone: update to linux 3.8

As the beaglebone support is mainlined, there's no support for the old
board setup files, and the only supported run-time configuration is through
the device tree.

We're also setting the kernel headers to follow the 3.8 series.

Signed-off-by: Anders Darander <anders@chargestorm.se>
am33x-cm3: add FW for suspend/resume

Without this firmware, the beaglebone won't be able to reboot correctly.

Signed-off-by: Anders Darander <anders@chargestorm.se>
beaglebone: add am33x-cm3 to the build

Add the FW needed for the Cortex M3 on the beaglebone. This is required for
a working power management.

Signed-off-by: Anders Darander <anders@chargestorm.se>
beaglebone: enable NFS root

Signed-off-by: Anders Darander <anders@chargestorm.se>