Initialize the /data encryption options only once

Cache the EncryptionOptions for /data in a static variable so that it
doesn't have to be repeatedly regenerated from the fstab.

Bug: 232452368
Bug: 251131631
Bug: 251147505
Ignore-AOSP-First: depends on other changes in internal master
Change-Id: I24b27190ed807f142b793d3cf250ec271d092f34
1 file changed