ARM: dts: msm: Update memory layout for MSM 8909

Memory map has been updated so as to support
different DRAM configuration such as 256 MB,
512 MB and 1 GB with same memory layout. Make
the corresponding change in base addresses and size
to reflect the changes.

Change-Id: Iee8cc38d9b5064fb9eb77ddedea1ff42bae0eaaf
Signed-off-by: Susheel Khiani <skhiani@codeaurora.org>