COMPMID-3851: Fix output quantization info for SoftmaxLayerNode

Signed-off-by: Sheri Zhang <sheri.zhang@arm.com>
Change-Id: I74b9495dcfcee619fda6f781845711c71eaaa5a6
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/4306
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/graph/nodes/SoftmaxLayerNode.cpp b/src/graph/nodes/SoftmaxLayerNode.cpp
index fb907f4..0311669 100644
--- a/src/graph/nodes/SoftmaxLayerNode.cpp
+++ b/src/graph/nodes/SoftmaxLayerNode.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 Arm Limited.
+ * Copyright (c) 2018-2020 Arm Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -64,7 +64,7 @@
     ARM_COMPUTE_ERROR_ON(src == nullptr);
 
     TensorDescriptor out_desc = src->desc();
-    out_desc.quant_info       = QuantizationInfo(1.f / 256.f, 0);
+    out_desc.quant_info       = get_softmax_output_quantization_info(out_desc.data_type, false);
 
     return out_desc;
 }