Move libneuralnetworks.so to com.android.neuralnetworks APEX

Test: build&flashed crosshatch image
Bug: 137320025

Change-Id: Iadbb32cffc636c515a5e89b62539183ebc0c2f14
diff --git a/core/main.mk b/core/main.mk
index 9182fa7..100099a 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -1244,6 +1244,7 @@
   libnativebridge.so \
   libnativehelper.so \
   libnativeloader.so \
+  libneuralnetworks.so \
   libnpt.so \
   libopenjdk.so \
   libopenjdkjvm.so \