ARM: dts: msm: Add Interposer device tree for MSM8994

Add the baseline device tree files needed to support the
MSM8994 Interposer CDP target.

Change-Id: I7b44e0fa1f86a8eaffc8c2076689b943edd48b39
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: David Keitel <dkeitel@codeaurora.org>