ARM: dts: msm: Add support for complete subsystem ramdump for SDM660

Add support to dump complete ramdump of subsystem from start of first
segment to end of last segment without leaving any hole in between.

Change-Id: I0bcab1d4e04748d3934b7a4d99eec59727c3afb1
Signed-off-by: Naitik Bharadiya <bharad@codeaurora.org>