IVGCVSW-5394 TfLiteDelegate: Implement the Lstm operator

 * Add LSTM operator

Signed-off-by: Mike Kelly <mike.kelly@arm.com>
Signed-off-by: Sadik Armagan <sadik.armagan@arm.com>
Change-Id: If8c667685fa1176738ffe2e6d08b1c684e7ee6b2
diff --git a/delegate/CMakeLists.txt b/delegate/CMakeLists.txt
index 7de168f..981fc9f 100644
--- a/delegate/CMakeLists.txt
+++ b/delegate/CMakeLists.txt
@@ -137,6 +137,8 @@
         src/test/GatherTestHelper.hpp
         src/test/LogicalTest.cpp
         src/test/LogicalTestHelper.hpp
+        src/test/LstmTest.cpp
+        src/test/LstmTestHelper.hpp
         src/test/NormalizationTest.cpp
         src/test/NormalizationTestHelper.hpp
         src/test/PadTest.cpp