file_contexts: remove files that do not exist under /data

Change-Id: I437b0e1babf3b974a9f7ca142f2fcff7d19bb6d0
camera: cleanup overlays

* Removed Focal overlay
* Removed Camera overlay (Additional iso & scene modes are merged in Gallery2 now)

Change-Id: I1f06f058823c9d96c314bab4b4f735669da7d152
Signed-off-by: Arnav Gupta <championswimmer@aokp.co>

Conflicts:
	overlay/packages/apps/Camera/res/values/arrays.xml
	overlay/packages/apps/Camera/res/values/strings.xml