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/ArmnnDriver.hpp b/ArmnnDriver.hpp
index fd5cfad..7c6e5d0 100644
--- a/ArmnnDriver.hpp
+++ b/ArmnnDriver.hpp
@@ -9,7 +9,7 @@
 
 #include <log/log.h>
 
-#if defined(ARMNN_ANDROID_NN_V1_1)
+#ifdef ARMNN_ANDROID_NN_V1_1 // Using ::android::hardware::neuralnetworks::V1_1
 
 #include "1.1/ArmnnDriver.hpp"
 
@@ -29,7 +29,7 @@
 
 } // namespace armnn_driver
 
-#else // Fallback to ::android::hardware::neuralnetworks::V1_0.
+#else // Fallback to ::android::hardware::neuralnetworks::V1_0
 
 #include "1.0/ArmnnDriver.hpp"