Improve javadocs for new S constants

- Distinguish between PROVISIONING_TRIGGER_PERSISTENT_DEVICE_OWNER
and PROVISIONING_TRIGGER_MANAGED_ACCOUNT
- Explain difference between
PROVISIONING_MODE_MANAGED_PROFILE_ON_PERSONAL_DEVICE and
PROVISIONING_MODE_MANAGED_PROFILE
- Improve deprecation message for ACTION_PROVISION_MANAGED_DEVICE

Test: compiled
Fixes: 179709752
Change-Id: Id56316982581cf98dab78ef0b09c9243960d2893