compatible with what our code assumed (pointers to objects of
TraceEntry and its POD base class trace_entry aren't identical
anymore).
* Added optional stack traces for ktrace_printf() output in the kernel.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@25531 a95241bf-73f2-0310-859d-f6bbb57e9c96