[turbofan] Add an InterpreterDispatch linkage type.

src/compiler/ia32/linkage-ia32.cc

Index: src/compiler/ia32/linkage-ia32.cc
diff --git a/src/compiler/ia32/linkage-ia32.cc b/src/compiler/ia32/linkage-ia32.cc
index 930a86c69f9b5b72e8f0344d911fc8556f0290db..7ea80b296203f9e7a7224de8161dda90aafff11f 100644
--- a/src/compiler/ia32/linkage-ia32.cc
+++ b/src/compiler/ia32/linkage-ia32.cc
@@ -60,6 +60,12 @@ CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
   return LH::GetSimplifiedCDescriptor(zone, sig);
 }
 
+
+CallDescriptor* Linkage::GetInterpreterDispatchDescriptor(
+    Zone* zone, const MachineSignature* sig) {
+  return LH::GetInterpreterDispatchDescriptor(zone, sig);
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8