treewide: support yocto kirkstone release

* Deprecate N-1 release (hardknott).
* Enable N+1 release (kirkstone).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I39e027e02dab64b4390b46ffbd9c299c858f403e
diff --git a/meta-facebook/meta-bletchley/conf/layer.conf b/meta-facebook/meta-bletchley/conf/layer.conf
index 14d3200..118ee30 100644
--- a/meta-facebook/meta-bletchley/conf/layer.conf
+++ b/meta-facebook/meta-bletchley/conf/layer.conf
@@ -8,4 +8,4 @@
 BBFILE_COLLECTIONS += "bletchley-layer"
 BBFILE_PATTERN_bletchley-layer := "^${LAYERDIR}/"
 
-LAYERSERIES_COMPAT_bletchley-layer := "hardknott honister"
+LAYERSERIES_COMPAT_bletchley-layer := "honister kirkstone"