[llvm] Add support for PSV EntryFunctionName (PR #84409)

[Cooper Partin via llvm-commits]

================
@@ -162,6 +97,94 @@ void PSVRuntimeInfo::write(raw_ostream &OS, uint32_t Version) const {
                                llvm::endianness::little);
 }
 
+static constexpr size_t npos = StringRef::npos;
----------------
coopp wrote:

Yes!  I can fix this up!

https://github.com/llvm/llvm-project/pull/84409