gh-133296: Fix versionadded for C API functions that were backported (#137024)

Author: ngoldbaum

Doc/c-api/init.rst

@@ -2287,7 +2287,7 @@ The C-API provides a basic mutual exclusion lock.
       should not be used to make concurrency control decisions, as the lock
       state may change immediately after the check.
 
-   .. versionadded:: next
+   .. versionadded:: 3.14
 
 .. _python-critical-section-api:
 
@@ -2372,7 +2372,7 @@ code triggered by the finalizer blocks and calls :c:func:`PyEval_SaveThread`.
 
    On the default build, this macro expands to ``{``.
 
-   .. versionadded:: next
+   .. versionadded:: 3.14
 
 .. c:macro:: Py_END_CRITICAL_SECTION()
 
@@ -2418,7 +2418,7 @@ code triggered by the finalizer blocks and calls :c:func:`PyEval_SaveThread`.
 
    On the default build, this macro expands to ``{``.
 
-   .. versionadded:: next
+   .. versionadded:: 3.14
 
 .. c:macro:: Py_END_CRITICAL_SECTION2()
 

Doc/whatsnew/3.14.rst

@@ -3035,6 +3035,7 @@ Porting to Python 3.14
   * ``_Py_GetConfig()``: :c:func:`PyConfig_Get` and :c:func:`PyConfig_GetInt`
   * ``_Py_HashBytes()``: :c:func:`Py_HashBuffer`
   * ``_Py_fopen_obj()``: :c:func:`Py_fopen`
+  * ``PyMutex_IsLocked()`` : :c:func:`PyMutex_IsLocked`
 
   The `pythoncapi-compat project`_ can be used to get most of these new
   functions on Python 3.13 and older.

Doc/whatsnew/3.15.rst

@@ -504,8 +504,6 @@ Porting to Python 3.15
 
 * Private functions promoted to public C APIs:
 
-  * ``PyMutex_IsLocked()`` : :c:func:`PyMutex_IsLocked`
-
   The |pythoncapi_compat_project| can be used to get most of these new
   functions on Python 3.14 and older.