dbg: fix parsing mangled func-name

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42404 4005530d-fff6-0310-9dd1-cebe43e6787f
dbg: add basic support for gdbserver

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@42405 4005530d-fff6-0310-9dd1-cebe43e6787f