arm/dt: 8974: Use SoC-specific DTSI files for v1/v2

The hardware differences between the MSM8974v1 and
MSM8974v2 SoCs necessitate the use of two separate device
trees. Create msm8974-v1 and msm8974-v2 wrappers around
msm8974.dtsi and update DTS files accordingly.

Change-Id: I4470c389f48d7be3cf3d1b307f9281c0529b9a71
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
8 files changed