port ldmp tool to 64-bit

_From [derek.br...@gmail.com](https://code.google.com/u/117968039472581148324/) on April 12, 2009 00:16:18_

this was PR 249988

This issue covers updating our core dump and the corresponding tools/ldmp.c
tool:
- GET_OWN_CONTEXT(), etc.
- os_dump_\* and ldmp.c: coordinate xax, r8 - r15 changes
- ldmp.c scanf of pointer types

xref issue #28 and issue #62 on other tool ports

_Original issue: http://code.google.com/p/dynamorio/issues/detail?id=118_

Start with tools/ldmp.c and the core-dump code around GET_OWN_CONTEXT(), os_dump_* and the xax and r8-r15 handling. Check how ldmp.c scans pointer types and compare the related ports in issues #28 and #62. Done means the core dump format and ldmp tool work correctly on 64-bit systems.

Written by the indexing model from the issue text.