simplify check

Author: Fidget-Spinner

Python/optimizer_bytecodes.c

@@ -524,9 +524,7 @@ dummy_func(void) {
     }
 
     op(_POP_TOP_FLOAT, (value -- )) {
-        if (PyJitRef_IsBorrowed(value) ||
-            sym_is_immortal(PyJitRef_Unwrap(value)) ||
-            sym_is_null(value)) {
+        if (PyJitRef_IsBorrowed(value)) {
             REPLACE_OP(this_instr, _POP_TOP_NOP, 0, 0);
         }
     }