fix bert precison bug

mindspore/ccsrc/device/ascend/kernel_select_ascend.cc

@@ -82,6 +82,12 @@ bool IsValidKernelInfo(const std::shared_ptr<CNode> &kernel_node, const kernel::
     }
     return true;
   };
+  if (AnfAlgo::GetCNodeName(kernel_node) == "LayerNormBetaGammaBackprop" ||
+      AnfAlgo::GetCNodeName(kernel_node) == "LayerNormXBackprop") {
+    if (AnfAlgo::GetPrevNodeOutputFormat(kernel_node, 0) != kernel_build_info.GetInputFormat(0)) {
+      return true;
+    }
+  }
   if (AnfAlgo::GetCNodeName(kernel_node) == prim::kPrimCast->name()) {
     return AnfAlgo::GetOutputInferDataType(kernel_node, 0) == kernel_build_info.GetOutputDeviceType(0) &&
            AnfAlgo::GetPrevNodeOutputInferDataType(kernel_node, 0) == kernel_build_info.GetInputDeviceType(0);
@@ -155,7 +161,7 @@ bool PriorityChooseItem(const std::vector<int> &cur_item, std::vector<int> *best
       return false;
     }
   }
-  return false;
+  return true;
 }
 
 void UpdateCurMatchCounts(const kernel::KernelBuildInfo &kernel_build_info, const std::shared_ptr<CNode> &kernel_node,