Arm backend: fix test for U55

Change-Id: I2bd38787378708ba8a05fc407d1de03cf6edd69a

Author: wwwind

backends/arm/test/ops/test_div_tensor_mode.py

@@ -77,7 +77,7 @@ def test_div_tensor_mode_tosa_INT(mode):
     pipeline.pop_stage("check_count.exir")
     pipeline.run()
 
-
+@common.XfailIfNoCorstone300
 @pytest.mark.parametrize("mode", [None, "floor"])
 def test_div_tensor_mode_u55_INT(mode):