Add support for the Broadcom BCM21664 mobile SoC. It has two Cortex-A9
cores like the BCM281xx family of chips. BCM21664 and BCM281xx share
many IP blocks in addition to the ARM cores.
Signed-off-by: Markus Mayer <markus.mayer@linaro.org>
Signed-off-by: Matt Porter <mporter@linaro.org>