IVGCVSW-4620 Add Fill Reference Implementation

 * Add Fill Reference Implementation
 * Refactor FP converter to use static_cast

Signed-off-by: Ryan OShea <Ryan.OShea2@arm.com>
Signed-off-by: Keith Davis <keith.davis@arm.com>
Change-Id: I532e2f982981d047690755fac43a0e9cf8b17dcd
diff --git a/src/backends/reference/workloads/RefWorkloads.hpp b/src/backends/reference/workloads/RefWorkloads.hpp
index e396a6b..951e3a1 100644
--- a/src/backends/reference/workloads/RefWorkloads.hpp
+++ b/src/backends/reference/workloads/RefWorkloads.hpp
@@ -34,6 +34,7 @@
 #include "RefDequantizeWorkload.hpp"
 #include "RefElementwiseWorkload.hpp"
 #include "RefElementwiseUnaryWorkload.hpp"
+#include "RefFillWorkload.hpp"
 #include "RefFullyConnectedWorkload.hpp"
 #include "RefFloorWorkload.hpp"
 #include "RefFakeQuantizationFloat32Workload.hpp"