ARM: dts: msm: 8916: Add node for the memory hole

The memory map for msm8916 has a region of memory that does not
belong to Linux. Add that information into the device tree.

Change-Id: I0f557ce6e1f7eb276425c62dcf88bc0ddd68d393
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>