rtems-tools: DWARF5 support in Elftoolchain

[Ryan Long]

Covoar has been unable to run after upgrading to GCC 12 because by 
default it generates DWARF5 debug info. Covoar uses libdwarf from 
Elftoolchain to read the debug info, and libdwarf only supports DWARF 
versions 2 through 4.

I submitted a ticket notifying Elftoolchain about this issue 
(https://sourceforge.net/p/elftoolchain/tickets/611/).


At the moment, you can get coverage to run just by going into 
rtems-tools/rtemstoolkit/elftoolchain/libdwarf/libdward_info.c at line 
228 and changing

cu->cu_version > 4

to

cu->cu_version > 5


Ryan