Currently only works on Linux + GDB.

See docs/ReactorDebugInfo.md for details.

Change-Id: I73d47d0492f6ccfc07eec4d4084332b4991fd515
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/27949
Presubmit-Ready: Ben Clayton <bclayton@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>