IDE: initial setup dialog: check gdb only if TGDBMIDebugger is selected

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@46938 4005530d-fff6-0310-9dd1-cebe43e6787f
lazdebugger: fixed typo

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@46939 4005530d-fff6-0310-9dd1-cebe43e6787f