Refactor inlined utility functions in NetworkUtils

Change-Id: I26fb13717f64c942b2648702c52be18be856042d
diff --git a/Android.mk b/Android.mk
index 988d6f0..3eeddcb 100644
--- a/Android.mk
+++ b/Android.mk
@@ -122,6 +122,7 @@
         src/armnn/Layer.cpp \
         src/armnn/LoadedNetwork.cpp \
         src/armnn/Network.cpp \
+        src/armnn/NetworkUtils.cpp \
         src/armnn/WallClockTimer.cpp \
         src/armnn/ProfilingEvent.cpp \
         src/armnn/Profiling.cpp \