[turbofan] Add DebugBreak machine operator and support

src/compiler/machine-operator.h

Index: src/compiler/machine-operator.h
diff --git a/src/compiler/machine-operator.h b/src/compiler/machine-operator.h
index 814f6c9bed1c9de10512efb54a44350e7b71df04..ed2a758b086e6de240ed907d93c59980558c7f97 100644
--- a/src/compiler/machine-operator.h
+++ b/src/compiler/machine-operator.h
@@ -128,6 +128,8 @@ class MachineOperatorBuilder final : public ZoneObject {
       MachineRepresentation word = MachineType::PointerRepresentation(),
       Flags supportedOperators = kNoFlags);
 
+  const Operator* DebugBreak();
+
   const Operator* Word32And();
   const Operator* Word32Or();
   const Operator* Word32Xor();