Update vendored mimalloc to upstream dev3

Sync Objects/mimalloc and Include/internal/mimalloc with
microsoft/mimalloc dev3 (1ff2382, "fix profile timestamps"). Most of
the local edits previously carried in the vendored copy have been
merged upstream (forceinline declaration order, WASI page size,
quoted includes, MSan syscalls, Emscripten builtin allocator,
MI_NO_ALIGN_FALLBACK_WARNING, MI_NO_CXX_NEW_HANDLER, __ImageBase,
trailing whitespace). The FLS init assertion fix is dropped as CPython
no longer uses MI_WIN_INIT_USE_FLS.

Changes still carried on top of dev3 (proposed upstream):

- Fix build with MI_NO_THP after the MADV_NOHUGEPAGE change
- Fix -Wsign-compare warning when reading hpage_pmd_size
- Fix data race on the thread-done pthread key at process exit

CPython-specific change:

- Purge expired ranges on arena free, as in mimalloc v2, to keep the
  peak memory of short-running processes at v2 levels.

Define MI_NO_ALIGN_FALLBACK_WARNING in pycore_mimalloc.h, since the
vendored copy now has the upstream opt-out instead of the warning being
commented out.

Author: DinoV

Include/internal/pycore_mimalloc.h

@@ -17,6 +17,9 @@
 // CPython never uses mimalloc's C++ operator new APIs, so don't define a weak
 // std::get_new_handler() (_ZSt15get_new_handlerv) in libpython.
 #  define MI_NO_CXX_NEW_HANDLER 1
+// The aligned OS allocation fallback is benign, but its warning is printed to
+// stderr and breaks tests that check output (e.g. test_cmd_line under ASan).
+#  define MI_NO_ALIGN_FALLBACK_WARNING 1
 #  ifdef Py_GIL_DISABLED
 #    define MI_PRIM_THREAD_ID   _Py_ThreadId
 #    define MI_CPYTHON 1