consistently use Py_TYPE, Py_REFCNT, and correct initializer macros (#3563)

This no-op change makes 2.7 more consistent with 3.x to ease comparison and backports.
diff --git a/Modules/_sre.c b/Modules/_sre.c
index 6fd3aff..94b3d50 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -2712,8 +2712,8 @@
 };
 
 statichere PyTypeObject Pattern_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "_" SRE_MODULE ".SRE_Pattern",
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "_" SRE_MODULE ".SRE_Pattern",
     sizeof(PatternObject), sizeof(SRE_CODE),
     (destructor)pattern_dealloc, /*tp_dealloc*/
     0,                                  /* tp_print */
@@ -3952,8 +3952,8 @@
 };
 
 statichere PyTypeObject Scanner_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "_" SRE_MODULE ".SRE_Scanner",
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "_" SRE_MODULE ".SRE_Scanner",
     sizeof(ScannerObject), 0,
     (destructor)scanner_dealloc, /*tp_dealloc*/
     0,				/* tp_print */