meta-amd: update Yocto compat for gatesgarth

The next release of Yocto is soon and most of the upstream
layers have switched support strings for it.  Support layer
compat for gatesgarth (current) and dunsfell (previous).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ifd0a195c54ae6c84d4739b83efa6981545d12077
diff --git a/meta-ethanolx/conf/layer.conf b/meta-ethanolx/conf/layer.conf
index 0d9d81c..22fc7be 100644
--- a/meta-ethanolx/conf/layer.conf
+++ b/meta-ethanolx/conf/layer.conf
@@ -9,4 +9,4 @@
 BBFILE_PATTERN_ethanolx-layer = "^${LAYERDIR}/"
 BBFILE_PRIORITY_ethanolx-layer = "6"
 
-LAYERSERIES_COMPAT_ethanolx-layer = "warrior zeus dunfell"
+LAYERSERIES_COMPAT_ethanolx-layer = "dunfell gatesgarth"