Fix the compilation error for turbofan unsupported platform.

src/compiler/linkage.cc

Index: src/compiler/linkage.cc
diff --git a/src/compiler/linkage.cc b/src/compiler/linkage.cc
index f76bc6079025b9d4185b2cb33eb2e86fefefa32a..4b301f512f9afc5737d59676fb640c7c0c96bcbe 100644
--- a/src/compiler/linkage.cc
+++ b/src/compiler/linkage.cc
@@ -232,6 +232,12 @@ CallDescriptor* Linkage::GetJSCallDescriptor(int parameter_count, Zone* zone,
 }
 
 
+LinkageLocation Linkage::GetOsrValueLocation(int index) const {
+  UNIMPLEMENTED();
+  return LinkageLocation(-1);  // Dummy value
+}
+
+
 CallDescriptor* Linkage::GetRuntimeCallDescriptor(
     Runtime::FunctionId function, int parameter_count,
     Operator::Properties properties, Zone* zone) {