fingerprintd.te: neverallow fingerprint data file access

Only fingerprintd should be creating/reading/writing/etc from
/data/system/users/[0-9]+/fpdata(/.*)? . Add a neverallow rule
(compile time assertion + CTS test) to ensure no regressions.

Change-Id: I30261a4bd880f5c4f3d90d1686a6267f60bdd413