CDB: Pass referenced address in separate GDBMI field.

Use 'origaddr' as gdb does. Do not append address to watch value
if it is already contained in the value.
Fixes the currently grayed-out 'Open memory editor at referenced
address'.

Change-Id: I6f7cf5b7984f93606ad4bb0872348f51c73f9117
Reviewed-by: hjk <qthjk@ovi.com>