Add enableFsVerity function in VerityUtils.h

Bug: 218672709
Test: Replace "com.android.sepolicy.cert-release.der" -> "com.android.sepolicy.cert-debug.der" in
selinux.cpp > kSigningCertRelease, then manual tests

Change-Id: I5b1cd99200af2835aab58c2a5354494b74e71abc
2 files changed