IVGCVSW-3267 Add Arm NN front end support for the new Prelu Activation layer

 * Added new PreluLayer class
 * Made necessary changes to ILayerSupport, ILayerVisitor, etc.
 * Added unit tests

Change-Id: Ifcfb78e823bb5a245ed1dad15290d2f60115c882
Signed-off-by: Matteo Martincigh <matteo.martincigh@arm.com>
diff --git a/Android.mk b/Android.mk
index b5376ac..7f3080b 100644
--- a/Android.mk
+++ b/Android.mk
@@ -123,6 +123,7 @@
         src/armnn/layers/PermuteLayer.cpp \
         src/armnn/layers/Pooling2dLayer.cpp \
         src/armnn/layers/PreCompiledLayer.cpp \
+        src/armnn/layers/PreluLayer.cpp \
         src/armnn/layers/QuantizeLayer.cpp \
         src/armnn/layers/ReshapeLayer.cpp \
         src/armnn/layers/ResizeBilinearLayer.cpp \