IVGCVSW-3845 Add Reference FP16 support for required layers

* Working on layers required by FSRCNN, FCRN and DeepSpeaker
* Updates RefLayerSupport and RefWorkloadFactory methods
* Adds RefPadFloat16Workload
* Tested by successful execution of these networks on Reference FP16 backend

Signed-off-by: Matthew Jackson <matthew.jackson@arm.com>
Change-Id: I4817dca0a89bba6902f0feffc494b27a26a0ab2d
diff --git a/src/backends/reference/workloads/RefPadWorkload.cpp b/src/backends/reference/workloads/RefPadWorkload.cpp
index 5e59d83..c4b9dae 100644
--- a/src/backends/reference/workloads/RefPadWorkload.cpp
+++ b/src/backends/reference/workloads/RefPadWorkload.cpp
@@ -34,6 +34,7 @@
 }
 
 template class RefPadWorkload<DataType::Float32>;
+template class RefPadWorkload<DataType::Float16>;
 template class RefPadWorkload<DataType::QuantisedAsymm8>;
 template class RefPadWorkload<DataType::QuantisedSymm16>;