fast_flush kwarg of do_bench is removed

Differential Revision: D65444506

Pull Request resolved: #1222

benchmarks/quantized_training/benchmark_int8mm.py

@@ -6,7 +6,7 @@
 
 
 def bench_f(f, *args):
-    return do_bench(lambda: f(*args), fast_flush=False, return_mode="median")
+    return do_bench(lambda: f(*args), return_mode="median")
 
 
 shapes = [(sz, sz, sz) for sz in [1024, 2048, 4096]]