IVGCVSW-7854 Remove/rewrite asserts in the backends.

* Identify usages of ARMNN_ASSERT that should be proper exceptions.
* Change ARMNN_ASSERT in Doctests to CHECK.
* Verify any remaining assertions are reasonable.

Signed-off-by: Colm Donelan <colm.donelan@arm.com>
Change-Id: Ifd1f2a5a4bb60135e8654305035ec70e09c4dc2d
diff --git a/src/backends/reference/RefLayerSupport.cpp b/src/backends/reference/RefLayerSupport.cpp
index 40d243e..f97d03a 100644
--- a/src/backends/reference/RefLayerSupport.cpp
+++ b/src/backends/reference/RefLayerSupport.cpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2017-2023 Arm Ltd and Contributors. All rights reserved.
+// Copyright © 2017-2024 Arm Ltd and Contributors. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 
@@ -958,7 +958,6 @@
                                   "Reference concatenation: output type not supported");
     for (const TensorInfo* input : inputs)
     {
-        ARMNN_ASSERT(input != nullptr);
         supported &= CheckSupportRule(TypeAnyOf(*input, supportedTypes), reasonIfUnsupported,
             "Reference concatenation: input type not supported");
 
@@ -2629,7 +2628,6 @@
                                   "Reference stack: output type not supported");
     for (const TensorInfo* input : inputs)
     {
-        ARMNN_ASSERT(input != nullptr);
         supported &= CheckSupportRule(TypeAnyOf(*input, supportedTypes), reasonIfUnsupported,
             "Reference stack: input type not supported");