Rename quantized data types to remove ambiguity for signed/unsigned payloads

!android-nn-driver:2572

Change-Id: I8fe52ceb09987b3d05c539409510f535165455cc
Signed-off-by: Derek Lamberti <derek.lamberti@arm.com>
diff --git a/src/backends/reference/workloads/Decoders.hpp b/src/backends/reference/workloads/Decoders.hpp
index 9d41c9e..faabdcd 100644
--- a/src/backends/reference/workloads/Decoders.hpp
+++ b/src/backends/reference/workloads/Decoders.hpp
@@ -79,14 +79,14 @@
                 params.second,
                 params.first);
         }
-        case DataType::QuantisedAsymm8:
+        case DataType::QAsymmU8:
         {
             return std::make_unique<QASymm8Decoder>(
                 static_cast<const uint8_t*>(data),
                 info.GetQuantizationScale(),
                 info.GetQuantizationOffset());
         }
-        case DataType::QuantisedSymm16:
+        case DataType::QSymmS16:
         {
             return std::make_unique<QSymm16Decoder>(
                 static_cast<const int16_t*>(data),