add langdale to compatible layer

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I65febeeec11e6e5b40ee728f42cfbe77023dae1e
diff --git a/meta-ampere/conf/layer.conf b/meta-ampere/conf/layer.conf
index dd0027f..d6bce1e 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 = "honister kirkstone"
+LAYERSERIES_COMPAT_ampere-layer = "kirkstone langdale"