IVGCVSW-1806 More Android NN Driver refactoring

 * Changed #if defined to #ifdef
 * Simplified the Android ML namespace resolution
 * Fixed the relative path in some include directives

Change-Id: I46e46faff98559c8042c1a4b8b82007f462df57d
diff --git a/ModelToINetworkConverter.cpp b/ModelToINetworkConverter.cpp
index 1a63280..8bf84e9 100644
--- a/ModelToINetworkConverter.cpp
+++ b/ModelToINetworkConverter.cpp
@@ -167,7 +167,7 @@
 
 template class ModelToINetworkConverter<hal_1_0::HalPolicy>;
 
-#if defined(ARMNN_ANDROID_NN_V1_1)
+#ifdef ARMNN_ANDROID_NN_V1_1
 template class ModelToINetworkConverter<hal_1_1::HalPolicy>;
 #endif