ARM: dts: msm: Add smp2p entries for MSM8992

Add the smp2p entries to facilitate smp2p interprocessor communication
between apps and non-apps processors.

Change-Id: I28d39aaa657e9740b82f2dcff6f9eba77115a3c3
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>