MIPS: PowerTV: Base files for Cisco PowerTV platform

Add the Cisco Powertv cable settop box to the MIPS tree. This platform is
based on a MIPS 24Kc processor with various devices integrated on the same
ASIC. There are multiple models of this box, with differing configuration
but the same kernel runs across the product line.

Signed-off-by: David VomLehn <dvomlehn@cisco.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/132/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>