debug/dwarf: don't crash on negative range/rnglist offset
No test case because the problem can only happen for invalid data. Let
the fuzzer find cases like this.
Fixes #55948
Change-Id: I7ba40ba928d2a14d4ac5b39f966173f3868d4729
Reviewed-on: https://go-review.googlesource.com/c/go/+/436876
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com> Reviewed-by: Than McIntosh <thanm@google.com>