[clang][bytecode][NFC] Remove unused function (#125201)

... and an unused include.

Author: tbaederr

clang/lib/AST/ByteCode/EvalEmitter.h

@@ -17,7 +17,6 @@
 #include "InterpState.h"
 #include "PrimType.h"
 #include "Source.h"
-#include "llvm/Support/Error.h"
 
 namespace clang {
 namespace interp {
@@ -42,8 +41,6 @@ class EvalEmitter : public SourceMapper {
   /// Clean up all resources.
   void cleanup();
 
-  InterpState &getState() { return S; }
-
 protected:
   EvalEmitter(Context &Ctx, Program &P, State &Parent, InterpStack &Stk);