bpo-42519: Replace PyMem_MALLOC() with PyMem_Malloc() (GH-23586)

No longer use deprecated aliases to functions:

* Replace PyMem_MALLOC() with PyMem_Malloc()
* Replace PyMem_REALLOC() with PyMem_Realloc()
* Replace PyMem_FREE() with PyMem_Free()
* Replace PyMem_Del() with PyMem_Free()
* Replace PyMem_DEL() with PyMem_Free()

Modify also the PyMem_DEL() macro to use directly PyMem_Free().
diff --git a/Modules/cjkcodecs/multibytecodec.c b/Modules/cjkcodecs/multibytecodec.c
index 8640276..37a80a7 100644
--- a/Modules/cjkcodecs/multibytecodec.c
+++ b/Modules/cjkcodecs/multibytecodec.c
@@ -1191,13 +1191,13 @@ _multibytecodec_MultibyteIncrementalDecoder_decode_impl(MultibyteIncrementalDeco
         goto errorexit;
 
     if (wdata != data)
-        PyMem_Del(wdata);
+        PyMem_Free(wdata);
     Py_XDECREF(buf.excobj);
     return res;
 
 errorexit:
     if (wdata != NULL && wdata != data)
-        PyMem_Del(wdata);
+        PyMem_Free(wdata);
     Py_XDECREF(buf.excobj);
     _PyUnicodeWriter_Dealloc(&buf.writer);
     return NULL;