Add support to configure double line clock in lockscreen [2/2]

This keeps the Settings entry under Lockscreen Settings for
Double line clock to be configurable.

As a result, this is now consistent with previous Android versions.

Co-authored-by: Luca Weiss <luca.weiss@fairphone.com>
Bug: 277244307
Test: atest SettingsRoboTests:com.android.settings.display.LockscreenClockPreferenceControllerTest
Change-Id: I08121a1a658cb4045aa30d0bd93e18ca22c3db6d