Adjust overlay for Trebuchet

- Config item "is_large_screen" is not needed for tilapia
- Please see http://review.cyanogenmod.org/#/c/29745/

Change-Id: I35268261a5a00d7a9309ff3f7c656aa12f8c5585
Merge remote-tracking branch 'upstream/cm-10.1' into cm-10.1