iCloud Restore option no longer display in activation process for DEP in iOS11, if the DEP profile in MDM has being set to skip “Sign in with Apple ID and iCloud”.
If this step is skipped in the DEP enrollment process, device will only be showing “Restore from iTunes” and “Setup as New Device”.
By allowing user to sign in with Apple ID and iCloud in the DEP profile, The restore page will detect that an iCloud account is signed in and present the restore with iCloud backup option.