Don't create one-handed-background-panel after rotation

From code flow, when onConfigurationChanged() by rotating
OneHandedBackgroundPanelOrganizer#showBackgroundPanelLayer()
will be invoked and then create one-handed-background-panel
even though OHM is not activated.
Besides, this could introduce overhead on SF.

Test: manual rotate and dumpsys check HWC layers
Test: atest WMShellUnitTests
Bug: 196306312
Change-Id: Ia766078d5c76b08ab5b24e0ce965ad1d085e4686