gh-122860: Remove unused macro `_Py_atomic_load_relaxed_int32` (#122861)

Python/ceval_gil.c

diff --git a/Python/ceval_gil.c b/Python/ceval_gil.c
index 0b45cab..6f4476d 100644
--- a/Python/ceval_gil.c
+++ b/Python/ceval_gil.c
@@ -49,13 +49,6 @@
      (Note: this mechanism is enabled with FORCE_SWITCHING above)
 */
 
-// GH-89279: Force inlining by using a macro.
-#if defined(_MSC_VER) && SIZEOF_INT == 4
-#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) (assert(sizeof((ATOMIC_VAL)->_value) == 4), *((volatile int*)&((ATOMIC_VAL)->_value)))
-#else
-#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) _Py_atomic_load_relaxed(ATOMIC_VAL)
-#endif
-
 // Atomically copy the bits indicated by mask between two values.
 static inline void
 copy_eval_breaker_bits(uintptr_t *from, uintptr_t *to, uintptr_t mask)

Python/ceval_macros.h

diff --git a/Python/ceval_macros.h b/Python/ceval_macros.h
index 2881ed2..8b25a5f 100644
--- a/Python/ceval_macros.h
+++ b/Python/ceval_macros.h
@@ -375,13 +375,6 @@ do { \
 } while (0);
 
 
-// GH-89279: Force inlining by using a macro.
-#if defined(_MSC_VER) && SIZEOF_INT == 4
-#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) (assert(sizeof((ATOMIC_VAL)->_value) == 4), *((volatile int*)&((ATOMIC_VAL)->_value)))
-#else
-#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) _Py_atomic_load_relaxed(ATOMIC_VAL)
-#endif
-
 static inline int _Py_EnterRecursivePy(PyThreadState *tstate) {
     return (tstate->py_recursion_remaining-- <= 0) &&
         _Py_CheckRecursiveCallPy(tstate);