ARM: dts: msm: Add a baseline device tree for msm8996 vplatform

The baseline device tree is for firmware update on msm8996 virtual
platform. It does not need any peripheral.

Change-Id: I080038a03b7dc484f6149f8c832374ee6def031b
Signed-off-by: Zhiqiang Tu <ztu@codeaurora.org>