Revert "Optionally allow unknown symbols in the backtrace tests"

This reverts commit f9971cb422df39adea7e8c7e22689b879e39c626.

Allowing no symbol resolving at all makes it too hard to see
whether the test actually tests anything.

But do keep "address out of range" as allowed error in check_err.
This can be interpreted as DWARF not available (if end of callstack
marker is missing, which it unfortunately often is missing even if CFI
is available.).

Signed-off-by: Mark Wielaard <mark@klomp.org>
3 files changed