Bug: 64905218
Test: device boots with /mnt/vendor present and selinux label
mnt_vendor_file applied correctly.
Change-Id: Ib34e2859948019d237cf2fe8f71845ef2533ae27
Merged-In: Ib34e2859948019d237cf2fe8f71845ef2533ae27
(cherry picked from commit 210a805b)