meta-resin-raspberrypi:layer.conf: Define LAYERSERIES_COMPAT
meta-resin-raspberrypi:layer.conf: Define LAYERSERIES_COMPAT

We avoid in this way a build warning. See:
https://patchwork.openembedded.org/patch/140542/

Signed-off-by: Andrei Gherzan <8dc7c09356db0b1762fb140617d7375c0a5a4131@resin.io>

resin-os/resin-raspberrypi,resin-os/resin-raspberrypi