[master] Initialize base_obj in constructor (cppcheck report)

src/lib/python/isc/datasrc/zonetable_accessor_python.cc

@@ -34,7 +34,11 @@ namespace {
 // The s_* Class simply covers one instantiation of the object
 class s_ZoneTableAccessor : public PyObject {
 public:
-    s_ZoneTableAccessor() : cppobj(ConstZoneTableAccessorPtr()) {};
+    s_ZoneTableAccessor() :
+        cppobj(ConstZoneTableAccessorPtr()),
+        base_obj(NULL)
+    {}
+
     ConstZoneTableAccessorPtr cppobj;
     // This is a reference to a base object; if the object of this class
     // depends on another object to be in scope during its lifetime,