[compiler-rt] [llvm] [WebAssembly] Remove `__c_longjmp` from compiler-rt (PR #185798)

[Heejin Ahn via llvm-commits]

aheejin wrote:

@sbc100 When we merge this downstream in emscripten, where do you plan to add `__c_longjmp` then?

https://github.com/llvm/llvm-project/pull/185798