Revert "[CodeGen] Keep track of eagerly emitted globals"

The added test doesn't work on Windows:
https://lab.llvm.org/buildbot/#/builders/216/builds/25769

This reverts commit f8dadef.

Author: hahnjo

clang/lib/CodeGen/CodeGenModule.cpp

@@ -3658,7 +3658,6 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
   if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) {
     // Emit the definition if it can't be deferred.
     EmitGlobalDefinition(GD);
-    addEmittedDeferredDecl(GD);
     return;
   }