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-google/conf/layer.conf b/meta-google/conf/layer.conf
index 8048658..e4f0f19 100644
--- a/meta-google/conf/layer.conf
+++ b/meta-google/conf/layer.conf
@@ -14,5 +14,5 @@
 BBFILE_COLLECTIONS += "google-layer"
 BBFILE_PATTERN_google-layer := "^${LAYERDIR}/"
 LAYERVERSION_google-layer = "1"
-LAYERSERIES_COMPAT_google-layer = "hardknott honister"
+LAYERSERIES_COMPAT_google-layer = "honister kirkstone"
 LAYERDEPENDS_google-layer += "core phosphor-layer"