Add NNAPI processes to ANR

Bug: 145388549
Test: manually as described below

Tested by causing a hang on a NNAPI-based app and checking NNAPI
processes dumps in ANR report.

Process:

- adb shell am hang --allow-restart
- adb pull /data/anr/*
- grep neuralnetworks anr_* | wc -l
- Verify count is >0 when run on a device flashed with this CL in.

Change-Id: I17eef38fda6332d5af4f2d946619a5a84c208c2d