Fix oatdump crash on arm64/arm code.

Also adds 16 bit literal information.

Rationale:
When "run-away" instructions are disassembled, the literal
addresses may go out of range, causing oatdump to crash.
This CL guards memory access against the full memory range
allocated to assembly instructions and data (it is possible
but not really necessary to refine this a bit). Out of range
arguments are now displayed as (?) to denote the issue, which
is a lot nicer than crashing.

BUG=28670871

Change-Id: I51e9b6a6a99162546fe31059f14278e8980451c2