IVGCVSW-5508 Activate compiler warnings in ArmNN TfLite Delegate

Signed-off-by: Finn Williams <Finn.Williams@arm.com>
Change-Id: I1a8e2aa618ff693c61010e6150f3ca41b8ab1201
diff --git a/delegate/src/test/Pooling2dTestHelper.hpp b/delegate/src/test/Pooling2dTestHelper.hpp
index a344650..f107d94 100644
--- a/delegate/src/test/Pooling2dTestHelper.hpp
+++ b/delegate/src/test/Pooling2dTestHelper.hpp
@@ -191,7 +191,7 @@
     auto armnnDelegateOutputData = armnnDelegateInterpreter->typed_tensor<T>(armnnDelegateOutputId);
     auto armnnDelegateOutputTensor = armnnDelegateInterpreter->tensor(armnnDelegateOutputId);
 
-    for (size_t i = 0; i < tfLiteDelegateOutputTensor->dims->size; i++)
+    for (size_t i = 0; i < static_cast<size_t>(tfLiteDelegateOutputTensor->dims->size); i++)
     {
         CHECK(outputShape[i] == armnnDelegateOutputTensor->dims->data[i]);
         CHECK(tfLiteDelegateOutputTensor->dims->data[i] == armnnDelegateOutputTensor->dims->data[i]);