PCIe memory address space is 1:1 mapped with u-boot.

Update dts of Px020RDB i.e. P1020RDB and P2020RDB to match the address map
changes in u-boot.
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>