IVGCVSW-2092 Port LSTMCell::Eval to ArmNN

 * Refactored the LSTM unit tests to avoid unnecessary copies
 * Added new AddTensorOperand convenience function
 * Fixed some required arguments in some tests
 * Added new files to Android.bp

!armnn:124

Change-Id: I77ed22f2692d8aa46884b9ee31e48403f7299545
diff --git a/Android.bp b/Android.bp
index 5911f69..4b76fe4 100644
--- a/Android.bp
+++ b/Android.bp
@@ -130,6 +130,8 @@
         "clframework/src/core/CL/kernels/CLWarpPerspectiveKernel.cpp",
         "clframework/src/core/CL/kernels/CLWeightsReshapeKernel.cpp",
         "clframework/src/core/CL/kernels/CLWidthConcatenateLayerKernel.cpp",
+        "clframework/src/core/CL/kernels/CLWidthConcatenate2TensorsKernel.cpp",
+        "clframework/src/core/CL/kernels/CLWidthConcatenate4TensorsKernel.cpp",
         "clframework/src/core/CL/kernels/CLWinogradFilterTransformKernel.cpp",
         "clframework/src/core/CL/kernels/CLWinogradInputTransformKernel.cpp",
         "clframework/src/core/CL/kernels/CLWinogradOutputTransformKernel.cpp",