Fix autoquant do_bench import (pytorch#162)

Just checking to see if CI passes

I might need to think a bit harder about nightly flags

torchao/quantization/autoquant.py

@@ -10,7 +10,11 @@
     safe_int_mm,
 )
 import torch.nn.functional as F
-from torch._inductor.utils import do_bench
+try:
+    from torch._inductor.utils import do_bench
+except:
+    from torch._inductor.runtime.runtime_utils import do_bench
+
 aten = torch.ops.aten
 
 AUTOQUANT_CACHE = {}