ARM: dts: msm: Enable dload_type selection on SM8150

Add dload_type device tree node to allow support for
selecting whether a full ramdump, minidump, or both
should be collected from a target.

Change-Id: I314ded251928364f0f8b106964ebd45294a389fc
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>