[3.14] Docs: Fix mimalloc allocator values and typos in C API init docs (GH-160666) (#160741)

(cherry picked from commit 210e7ab)

Author: manoj-marimuthu

Doc/c-api/init_config.rst

@@ -880,9 +880,9 @@ PyPreConfig
       * ``PYMEM_ALLOCATOR_PYMALLOC_DEBUG`` (``6``): :ref:`Python pymalloc
         memory allocator <pymalloc>` with :ref:`debug hooks
         <pymem-debug-hooks>`.
-      * ``PYMEM_ALLOCATOR_MIMALLOC`` (``6``): use ``mimalloc``, a fast
+      * ``PYMEM_ALLOCATOR_MIMALLOC`` (``7``): use ``mimalloc``, a fast
         malloc replacement.
-      * ``PYMEM_ALLOCATOR_MIMALLOC_DEBUG`` (``7``): use ``mimalloc``, a fast
+      * ``PYMEM_ALLOCATOR_MIMALLOC_DEBUG`` (``8``): use ``mimalloc``, a fast
         malloc replacement with :ref:`debug hooks <pymem-debug-hooks>`.