bpo-40137: Add pycore_moduleobject.h internal header (GH-25507)

Add pycore_moduleobject.h internal header file with static inline
functions to access module members:

* _PyModule_GetDict()
* _PyModule_GetDef()
* _PyModule_GetState()

These functions don't check at runtime if their argument has a valid
type and can be inlined even if Python is not built with LTO.

_PyType_GetModuleByDef() uses _PyModule_GetDef().

Replace PyModule_GetState() with _PyModule_GetState() in the
extension modules, considered as performance sensitive:

* _abc
* _functools
* _operator
* _pickle
* _queue
* _random
* _sre
* _struct
* _thread
* _winapi
* array
* posix

The following extensions are now built with the Py_BUILD_CORE_MODULE
macro defined, to be able to use the internal pycore_moduleobject.h
header: _abc, array, _operator, _queue, _sre, _struct.
diff --git a/Objects/moduleobject.c b/Objects/moduleobject.c
index e57ea86..a6eb85b 100644
--- a/Objects/moduleobject.c
+++ b/Objects/moduleobject.c
@@ -4,6 +4,7 @@
 #include "Python.h"
 #include "pycore_interp.h"        // PyInterpreterState.importlib
 #include "pycore_pystate.h"       // _PyInterpreterState_GET()
+#include "pycore_moduleobject.h"  // _PyModule_GetDef()
 #include "structmember.h"         // PyMemberDef
 
 static Py_ssize_t max_module_number;
@@ -12,15 +13,6 @@ _Py_IDENTIFIER(__doc__);
 _Py_IDENTIFIER(__name__);
 _Py_IDENTIFIER(__spec__);
 
-typedef struct {
-    PyObject_HEAD
-    PyObject *md_dict;
-    struct PyModuleDef *md_def;
-    void *md_state;
-    PyObject *md_weaklist;
-    PyObject *md_name;  /* for logging purposes after md_dict is cleared */
-} PyModuleObject;
-
 static PyMemberDef module_members[] = {
     {"__dict__", T_OBJECT, offsetof(PyModuleObject, md_dict), READONLY},
     {0}
@@ -469,14 +461,11 @@ PyModule_SetDocString(PyObject *m, const char *doc)
 PyObject *
 PyModule_GetDict(PyObject *m)
 {
-    PyObject *d;
     if (!PyModule_Check(m)) {
         PyErr_BadInternalCall();
         return NULL;
     }
-    d = ((PyModuleObject *)m) -> md_dict;
-    assert(d != NULL);
-    return d;
+    return _PyModule_GetDict(m);
 }
 
 PyObject*
@@ -556,7 +545,7 @@ PyModule_GetDef(PyObject* m)
         PyErr_BadArgument();
         return NULL;
     }
-    return ((PyModuleObject *)m)->md_def;
+    return _PyModule_GetDef(m);
 }
 
 void*
@@ -566,7 +555,7 @@ PyModule_GetState(PyObject* m)
         PyErr_BadArgument();
         return NULL;
     }
-    return ((PyModuleObject *)m)->md_state;
+    return _PyModule_GetState(m);
 }
 
 void