linux-ramdump-parser-v2: Don't use ram start address in socinfo

When reading soc info, the ram information has not yet been fully
plumbed into the parser (this is very early!). We should not take
the address for the start of ram into account at this point as smem
should only be given as an offset. Update the calculations.

Change-Id: Ib02db2f118685b306457e2591e4bbc5f19f2edbc