IVGCVSW-4485 Remove Boost assert

 * Change boost assert to armnn assert
 * Change include file to armnn assert
 * Fix ARMNN_ASSERT_MSG issue with multiple conditions
 * Change BOOST_ASSERT to BOOST_TEST where appropriate
 * Remove unused include statements

Signed-off-by: Narumol Prangnawarat <narumol.prangnawarat@arm.com>
Change-Id: I5d0fa3a37b7c1c921216de68f0073aa34702c9ff
diff --git a/src/backends/reference/workloads/Mean.cpp b/src/backends/reference/workloads/Mean.cpp
index f2c0a4f..72080ef 100644
--- a/src/backends/reference/workloads/Mean.cpp
+++ b/src/backends/reference/workloads/Mean.cpp
@@ -128,7 +128,7 @@
     for (unsigned int idx = 0; idx < numResolvedAxis; ++idx)
     {
         unsigned int current = inputDims[resolvedAxis[idx]];
-        BOOST_ASSERT(boost::numeric_cast<float>(current) <
+        ARMNN_ASSERT(boost::numeric_cast<float>(current) <
               (std::numeric_limits<float>::max() / boost::numeric_cast<float>(numElementsInAxis)));
         numElementsInAxis *= current;
     }