meta-yadro: add dunfell compatibility

OE-core is switching over to dunfell.
This adds dunfell compatibility for meta-yadro, meta-vesnin and
meta-ncole layers.

Change-Id: Id99d98da42b847efcb52215be9a2e3dafd3540eb
Signed-off-by: Alexander Filippov <a.filippov@yadro.com>
diff --git a/conf/layer.conf b/conf/layer.conf
index 09b216d..0a5f6f2 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -9,4 +9,4 @@
 BBFILE_PATTERN_yadro-layer = "^${LAYERDIR}/"
 BBFILE_PATTERN_IGNORE_EMPTY_yadro-layer = "1"
 
-LAYERSERIES_COMPAT_yadro-layer = "warrior zeus"
+LAYERSERIES_COMPAT_yadro-layer = "warrior zeus dunfell"