Allow neuralnetworks hal service to read files from /sdcard

Bug: 138457453
Test: tflite nnapi benchmark app against /sdcard file
Change-Id: I368629f9177141d59eb5862cd29dd65da68d3ad7
Merged-In: I368629f9177141d59eb5862cd29dd65da68d3ad7
(cherry picked from commit 94be98073d52a4e2eb417f3f7aeaec756034d447)
2 files changed