Fix another case where the type checker will set the correct types.

We should not be providing types that we can/should derive
automatically.

Author: rudkx

lib/Sema/DerivedConformanceEquatableHashable.cpp

@@ -173,11 +173,10 @@ static void deriveBodyEquatable_enum_eq(AbstractFunctionDecl *eqDecl) {
                                       fnType);
   }
 
-  auto tType = fnType.getInput();
   TupleExpr *abTuple = TupleExpr::create(C, SourceLoc(), { aIndex, bIndex },
                                          { }, { }, SourceLoc(),
                                          /*HasTrailingClosure*/ false,
-                                         /*Implicit*/ true, tType);
+                                         /*Implicit*/ true);
 
   auto *cmpExpr = new (C) BinaryExpr(cmpFuncExpr, abTuple, /*implicit*/ true);
   statements.push_back(new (C) ReturnStmt(SourceLoc(), cmpExpr));