vndk snapshot update: read txt file with utf-8 encoding

VNDK snapshot updater reads license text files. To avoid unexpected
text files to be read, explicitly set the encoding type and ignore
if failed to read.

Bug: 288846788
Test: add binary to read and see if it is ignored
Change-Id: I7e3d0bbdc6c692ef7dbc6d8bf9d53c67003d0f90
1 file changed