hardknott: yocto release

Latest upstream yocto has moved on to the 3.3 hardknott release

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: Ieae36798d66d21c2c642931f06407d3bb2acf163
diff --git a/meta-ampere/conf/layer.conf b/meta-ampere/conf/layer.conf
index 20fb0b2..800936b 100644
--- a/meta-ampere/conf/layer.conf
+++ b/meta-ampere/conf/layer.conf
@@ -7,4 +7,4 @@
 
 BBFILE_COLLECTIONS += "ampere-layer"
 BBFILE_PATTERN_ampere-layer := "^${LAYERDIR}/"
-LAYERSERIES_COMPAT_ampere-layer = "dunfell gatesgarth"
+LAYERSERIES_COMPAT_ampere-layer = "gatesgarth hardknott"