[lldb][test] Accept legacy register index overflow diagnostic (#233764)
[ARM builder was failing
](https://lab.llvm.org/buildbot/#/builders/18/builds/27896)after I
merged https://github.com/llvm/llvm-project/pull/224147
because `TestXMLRegisterUnion.py` expected the legacy expression parser
to report oversized vector indexes with array index, but on 32-bit ARM
the index `4294967296` overflows long during parsing first, so LLDB
reports invalid index expression `""` instead. The command still fails
correctly; only the test’s expected diagnostic was too specific.
Co-authored-by: Bar Soloveychik <barsolo@fb.com>
llvm-project
922869f0 - [lldb][test] Accept legacy register index overflow diagnostic (#233764)
