[clang] [clang][modules] Reset codegen options. (PR #74006)

[Juergen Ributzka via cfe-commits]

================
@@ -4770,9 +4770,20 @@ std::string CompilerInvocation::getModuleHash() const {
 
   // When compiling with -gmodules, also hash -fdebug-prefix-map as it
   // affects the debug info in the PCM.
-  if (getCodeGenOpts().DebugTypeExtRefs)
+  if (getHeaderSearchOpts().ModuleFormat == "obj") {
----------------
ributzka wrote:

I reverted this particular change, to preserve existing behavior. I created a separate if condition for my changes after this code.

https://github.com/llvm/llvm-project/pull/74006