[llvm] [GSYM] Add support for querying merged functions in llvm-gsymutil (PR #120991)

[Daniel Thornburgh via llvm-commits]

mysterymath wrote:

Hi, we're still seeing breakages in Fuchsia's Windows x64 toolchain builders, even after #121837 went in:

https://luci-milo.appspot.com/ui/p/fuchsia/builders/toolchain.ci/clang-host-windows-x64/b8726451909038653473/overview

`LLVM :: tools/llvm-gsymutil/ARM_AArch64/macho-merged-funcs-dwarf.yaml`

Might this test just need the same treatment?

https://github.com/llvm/llvm-project/pull/120991