Covoar address to line to DWARF updates.

[Chris Johns]

Hi,

I have pushed my latest set of changes to my personal repo to remove covoar
exec'ing addr2line and to directly use the DWARF debug info.

I have not been able to fully test the results because I do not have a suitable
.exe and .cov pair with match source. The executable and coverage data I have
received has helped but objdump fails because I do not have the source in the
executable path so does not find the source.

I would like to get these changes on to master as soon as possible so if a
covoar built from my repo can be tested I can then push the changes to master.

I have added to RTEMS Tools an addr2line utility as I needed a tool to test the
DWARF support I have added to the rtemstoolkit.

The repo is https://git.rtems.org/chrisj/rtems-tools.git and the changes are on
the branch 'covoar-dwarf'.

Thanks
Chris