Fix another stack assert on HP-PA (GH-140028)

Missed in GH-139914, as it was introduced around the same time and is
only relevant to pydebug builds.

Author: stefanor

Python/ceval.c

@@ -514,7 +514,11 @@ tstate_set_stack(PyThreadState *tstate,
                  uintptr_t base, uintptr_t top)
 {
     assert(base < top);
+#if _Py_STACK_GROWS_DOWN
     assert((top - base) >= _PyOS_MIN_STACK_SIZE);
+#else
+    assert((base - top) >= _PyOS_MIN_STACK_SIZE);
+#endif
 
 #ifdef _Py_THREAD_SANITIZER
     // Thread sanitizer crashes if we use more than half the stack.