IVGCVSW-5969 TfLiteDelegate: Add PACK operator Support

 * Added support for PACK which is equivalent to Arm NN STACK

Signed-off-by: Matthew Sloyan <matthew.sloyan@arm.com>
Change-Id: I9ea134d0310eeea1caba30a8b9221712e9487c75
diff --git a/delegate/CMakeLists.txt b/delegate/CMakeLists.txt
index 707877f..dc65a19 100644
--- a/delegate/CMakeLists.txt
+++ b/delegate/CMakeLists.txt
@@ -33,6 +33,7 @@
         src/LogicalBinary.hpp
         src/Lstm.hpp
         src/Normalization.hpp
+        src/Pack.hpp
         src/Pad.hpp
         src/Pooling.hpp
         src/Quantization.hpp
@@ -145,6 +146,8 @@
         src/test/LstmTestHelper.hpp
         src/test/NormalizationTest.cpp
         src/test/NormalizationTestHelper.hpp
+        src/test/PackTest.cpp
+        src/test/PackTestHelper.hpp
         src/test/PadTest.cpp
         src/test/PadTestHelper.hpp
         src/test/Pooling2dTest.cpp