DWARF: correct the range list iteration
DWARF: correct the range list iteration

The offset computation needs to account for the stride (4-bytes by
default in DWARF).  Account for the difference in stride width for
DWARF64, which uses a 8-byte stride.

Applied from 2151c24a333c448711a9d3ea0c201652988cd488

google/bloaty,google/bloaty,google/bloaty