Hide additional blacklist separator

When there is no blacklist func enabled we dont need
2 separators at the end of row

Change-Id: Ieef2d2b5f553c2b4dd48ae528e7a0de185f4b2ad
phone: Enable the blacklist by default

Change-Id: I0b2d3482d75abe9c9fc161f199782f27b9baa46b
phone: Set default preference values for blacklist option

Change-Id: Iac33c84e19f30dd78226989977af90891d65018a