[llvm] [DWARFVerifier] Fix debug_str_offsets DWARF version detection (PR #81303)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> However, the verifier supports some pre-standardization version of this section (with the same section name), which does not have a header. In this case, the offsets start on the first byte of the section, although it's not clear where this is documented.

https://gcc.gnu.org/wiki/DebugFission and https://gcc.gnu.org/wiki/DebugFissionDWP is where this pre-standard stuff was documented

https://github.com/llvm/llvm-project/pull/81303