[DebugInfo] Propagate source loc from invoke to replacement branch (#137206)
An existing transformation replaces invoke instructions with a call to
the invoked function and a branch to the destination; when this happens,
we propagate the invoke's source location to the call but not to the
branch. This patch updates this behaviour to propagate to the branch as
well.
Found using https://github.com/llvm/llvm-project/pull/107279.