Enforce the physical offset to be picked from boards config file.
Autodump feauture takes physical offset from ddr info files which
assumes kernel is loaded at ram start address. This is no longer a
valid assumption.

Change-Id: I0d55ce2f93198a802723017e2a9f64d0877f461c
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>