IVGCVSW-3888 Add INSTANCE_NORMALIZATION Reference implementation

Signed-off-by: Kevin May <kevin.may@arm.com>
Change-Id: I725022f86e990c482ea323fc90fd136fe493ed68
diff --git a/src/backends/reference/backend.mk b/src/backends/reference/backend.mk
index 597fba8..f45b015 100644
--- a/src/backends/reference/backend.mk
+++ b/src/backends/reference/backend.mk
@@ -34,6 +34,7 @@
         workloads/ElementwiseFunction.cpp \
         workloads/FullyConnected.cpp \
         workloads/Gather.cpp \
+        workloads/InstanceNorm.cpp \
         workloads/LstmUtils.cpp \
         workloads/Mean.cpp \
         workloads/Concatenate.cpp \
@@ -60,6 +61,7 @@
         workloads/RefFloorWorkload.cpp \
         workloads/RefFullyConnectedWorkload.cpp \
         workloads/RefGatherWorkload.cpp \
+        workloads/RefInstanceNormalizationWorkload.cpp \
         workloads/RefL2NormalizationWorkload.cpp \
         workloads/RefLstmWorkload.cpp \
         workloads/RefMeanWorkload.cpp \