bpo-40602: Rename hashtable.h to pycore_hashtable.h (GH-20044)
* Move Modules/hashtable.h to Include/internal/pycore_hashtable.h
* Move Modules/hashtable.c to Python/hashtable.c
* Python is now linked to hashtable.c. _tracemalloc is no longer
linked to hashtable.c. Previously, marshal.c got hashtable.c via
_tracemalloc.c which is built as a builtin module.
diff --git a/Modules/Setup b/Modules/Setup
index 6bf1424..87e73ba 100644
--- a/Modules/Setup
+++ b/Modules/Setup
@@ -132,7 +132,7 @@
#
# bpo-35053: The module must be builtin since _Py_NewReference()
# can call _PyTraceMalloc_NewReference().
-_tracemalloc _tracemalloc.c hashtable.c
+_tracemalloc _tracemalloc.c
# PEG-based parser module -- slated to be *the* parser
_peg_parser _peg_parser.c