NNXSW-1826 Add an optimization step which combines Permute and BatchToSpace into DepthToSpace

This is only possible in some limited cases, but removes an extra
layer from the graph and so should improve performance in all cases.

Change-Id: I7b3e6ba5dacb4fdb816ad270edaecda1436ab4cf
Signed-off-by: Rob Hughes <robert.hughes@arm.com>
diff --git a/Android.mk b/Android.mk
index 3e665a0..4c3789c 100644
--- a/Android.mk
+++ b/Android.mk
@@ -91,6 +91,7 @@
         src/armnn/NetworkUtils.cpp \
         src/armnn/Observable.cpp \
         src/armnn/Optimizer.cpp \
+        src/armnn/optimizations/PermuteAndBatchToSpaceAsDepthToSpace.cpp \
         src/armnn/ProfilingEvent.cpp \
         src/armnn/Profiling.cpp \
         src/armnn/Runtime.cpp \