ARM: dts: msm: Add device tree for APQ8084 MTP

Add a DTSI file and a top-level DTS file needed to support
the APQ8084 MTP platform in a dedicated DTS file.

Change-Id: I4ea775438539a160ae835493b4a7795832334a25
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>