Allow turning on screen even when in landscape.

Disabling locking when in landscape has a side-effect of not being able to turn the screen on should the screen be locked in landscabe by e.g. a time out or the user locking via the power button.

This change keeps the service running even when in landscape orientation and landscape locking is disabled. When about to lock the screen, a test is performed on the landscape preference and orientation to determine if the screen lock can proceed.