Remove stray typedef in _tkinter.c (GH-142924)

Co-authored-by: Michiel de Hoon <mdehoon@tkx288.genome.gsc.riken.jp>

Author: mdehoon

Modules/_tkinter.c

@@ -235,7 +235,6 @@ static PyThread_type_lock tcl_lock = 0;
 
 #ifdef TCL_THREADS
 static Tcl_ThreadDataKey state_key;
-typedef PyThreadState *ThreadSpecificData;
 #define tcl_tstate \
     (*(PyThreadState**)Tcl_GetThreadData(&state_key, sizeof(PyThreadState*)))
 #else