libmeminfo: Swap accounting bug fixes

This fixes a couple issues:
  1. Swap offsets are 50-bit wide, so store them in uint64_t instead of
     uint16_t.
  2. Swap offset starts from 1 instead of 0.  Add one extra slot in
     swap offset count array to account for this.

Test: Run procrank and does not see incorrect PSwap numbers anymore.
Change-Id: I2471970d4a29909e8a0874f6c69af3f9a0b15b02
4 files changed