[Metax] fix fail test when backend is mack (#1937)

Co-authored-by: chezhang <1376507468@qq.com>

Author: metax666

backends/metax_gpu/kernels/cuda_kernels/batch_norm_kernel_register.cc

@@ -20,4 +20,12 @@ PD_CUSTOM_KERNEL_REGISTER(batch_norm_infer,
                           ALL_LAYOUT,
                           phi::BatchNormInferKernel,
                           float,
-                          phi::dtype::float16) {}
+                          double,
+                          phi::dtype::bfloat16,
+                          phi::dtype::float16) {
+  if (kernel_key.dtype() == phi::DataType::FLOAT16 ||
+      kernel_key.dtype() == phi::DataType::BFLOAT16) {
+    kernel->OutputAt(1).SetDataType(phi::DataType::FLOAT32);
+    kernel->OutputAt(2).SetDataType(phi::DataType::FLOAT32);
+  }
+}