bpo-36301: Cleanup preconfig.c and coreconfig.c (GH-12563)

* _PyCoreConfig_Write() now updates _PyRuntime.preconfig
* Remove _PyPreCmdline_Copy()
* _PyPreCmdline_Read() now accepts _PyPreConfig and _PyCoreConfig
  optional configurations.
* Rename _PyPreConfig_ReadFromArgv() to _PyPreConfig_Read(). Simplify
  the code.
* Calling _PyCoreConfig_Read() no longer adds the warning options
  twice: don't add a warning option if it's already in the list.
* Rename _PyCoreConfig_ReadFromArgv() to _PyCoreConfig_Read().
* Rename config_from_cmdline() to _PyCoreConfig_ReadFromArgv().
* Add more assertions on _PyCoreConfig in _PyCoreConfig_Read().
* Move some functions.
* Make some config functions private.
diff --git a/Include/cpython/pylifecycle.h b/Include/cpython/pylifecycle.h
index e32e54c..0c5f74e 100644
--- a/Include/cpython/pylifecycle.h
+++ b/Include/cpython/pylifecycle.h
@@ -21,8 +21,8 @@
     const _PyCoreConfig *coreconfig);
 
 PyAPI_FUNC(_PyInitError) _Py_InitializeCore(
-    PyInterpreterState **interp,
-    const _PyCoreConfig *);
+    const _PyCoreConfig *config,
+    PyInterpreterState **interp);
 PyAPI_FUNC(int) _Py_IsCoreInitialized(void);