Add unstrippedOutputFilePath to the linker interface

Test: m
Change-Id: I85a0cbda6ebb9838451ed8c607c2087460b7b742

cc/object.go

@@ -107,3 +107,7 @@ func (object *objectLinker) link(ctx ModuleContext,
 	ctx.CheckbuildFile(outputFile)
 	return outputFile
 }
+
+func (object *objectLinker) unstrippedOutputFilePath() android.Path {
+	return nil
+}