IVGCVSW-5676 Fixing build failure in backends jenkins job.

* Adding ref backend "ifdef" around ref test cases in
  NeonLayerTests_NDK_Bug.cpp
* Removing unnecessary includes from NeonLayerTests_NDK_Bug.cpp.
* Removing unnecessary include from NeonLayerTests.cpp
* Breaking up Backends_Capability_Test into one per backend to allow
  for conditional compilation.
* Remove unnecessary printout in src/backends/neon/test/CMakeLists.txt

Signed-off-by: Colm Donelan <Colm.Donelan@arm.com>
Change-Id: I9a36cd197e684ed55af244e5c998ee67bb8da88c
diff --git a/src/backends/backendsCommon/test/CompatibilityTests.cpp b/src/backends/backendsCommon/test/CompatibilityTests.cpp
index 1c4ff70..915a015 100644
--- a/src/backends/backendsCommon/test/CompatibilityTests.cpp
+++ b/src/backends/backendsCommon/test/CompatibilityTests.cpp
@@ -119,15 +119,34 @@
 
 BOOST_AUTO_TEST_SUITE(BackendCapability)
 
-BOOST_AUTO_TEST_CASE(Backends_Capability_Test)
-{
-    auto neonBackend = std::make_unique<NeonBackend>();
-    auto clBackend   = std::make_unique<ClBackend>();
-    auto refBackend  = std::make_unique<RefBackend>();
+#if defined(ARMNNREF_ENABLED)
 
-    BOOST_CHECK(!neonBackend->HasCapability(armnn::BackendCapability::NonConstWeights));
-    BOOST_CHECK(!clBackend->HasCapability(armnn::BackendCapability::NonConstWeights));
+BOOST_AUTO_TEST_CASE(Ref_Backends_Capability_Test)
+{
+    auto refBackend  = std::make_unique<RefBackend>();
     BOOST_CHECK(refBackend->HasCapability(armnn::BackendCapability::NonConstWeights));
 }
 
+#endif
+
+#if defined(ARMCOMPUTENEON_ENABLED)
+
+BOOST_AUTO_TEST_CASE(Neon_Backends_Capability_Test)
+{
+    auto neonBackend = std::make_unique<NeonBackend>();
+    BOOST_CHECK(!neonBackend->HasCapability(armnn::BackendCapability::NonConstWeights));
+}
+
+#endif
+
+#if defined(ARMCOMPUTECL_ENABLED)
+
+BOOST_AUTO_TEST_CASE(Cl_Backends_Capability_Test)
+{
+    auto clBackend   = std::make_unique<ClBackend>();
+    BOOST_CHECK(!clBackend->HasCapability(armnn::BackendCapability::NonConstWeights));
+}
+
+#endif
+
 BOOST_AUTO_TEST_SUITE_END()