ARM: dts: msm: Expand the MPSS region on sdxpoorwills

As per the hardware specifications, the MPSS and the LPASS
regions are merged, and a common (merged) image is supplied.
The change expands the MPSS region to cover the LPASS region.

Change-Id: I02d5984c11b20277fc974192cc4916c82a19f8b1
Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>