imx: mx6sabresd: add i.MX6DQP Sabresd support

Add i.MX6DQP-Sabresd board support:
1. set fdt_file according to board_rev which is set at runtime.
2. Add mx6dqp_ddr_ioregs and calibration value for this board.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
2 files changed