[clang] [Clang][Parse] Fix crash on stmt-expr ending with 'extern void;' (PR #181579)

[Giovanni B. via cfe-commits]

Z3rox-dev wrote:

@ojhunt Thanks for the detailed review, really appreciate you taking the time. I’m reworking and rethinking the change to come back with a cleaner approach that addresses the points you raised, will push an update soon

https://github.com/llvm/llvm-project/pull/181579