powerpc/t4qds: Add T4QDS board

The T4240QDS is a high-performance computing evaluation, development and
test platform supporting the T4240 QorIQ Power Architecture™ processor.

SERDES Connections
  32 lanes grouped into four 8-lane banks
  Two “front side” banks dedicated to Ethernet
  Two “back side” banks dedicated to other protocols
DDR Controllers
  Three independant 64-bit DDR3 controllers
  Supports rates up to 2133 MHz data-rate
  Supports two DDR3/DDR3LP UDIMM/RDIMMs per controller
QIXIS System Logic FPGA

Each DDR controller has two DIMM slots. The first slot of each controller
has up to 4 chip selects to support single-, dual- and quad-rank DIMMs.
The second slot has only 2 chip selects to support single- and dual-rank
DIMMs. At any given time, up to total 4 chip selects can be used.

Detail information can be found in doc/README.t4qds

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>