meta-hpe: 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 dunfell (previous).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I88a0c0482f4395f7c5103e8b31f58151ba20139a
diff --git a/meta-dl360poc/conf/layer.conf b/meta-dl360poc/conf/layer.conf
index 4627564..ef937d3 100644
--- a/meta-dl360poc/conf/layer.conf
+++ b/meta-dl360poc/conf/layer.conf
@@ -7,4 +7,4 @@
 
 BBFILE_COLLECTIONS += "dl360poc-layer"
 BBFILE_PATTERN_dl360poc-layer := "^${LAYERDIR}/"
-LAYERSERIES_COMPAT_dl360poc-layer = "zeus warrior dunfell"
+LAYERSERIES_COMPAT_dl360poc-layer = "dunfell gatesgarth"
diff --git a/meta-gxp/conf/layer.conf b/meta-gxp/conf/layer.conf
index eafb7ba..af9f8af 100644
--- a/meta-gxp/conf/layer.conf
+++ b/meta-gxp/conf/layer.conf
@@ -7,6 +7,6 @@
 BBFILE_COLLECTIONS += "gxp-layer"
 BBFILE_PATTERN_gxp-layer = "^${LAYERDIR}/"
 LAYERVERSION_gxp-layer = "1"
-LAYERSERIES_COMPAT_gxp-layer = "zeus warrior dunfell"
+LAYERSERIES_COMPAT_gxp-layer = "dunfell gatesgarth"
 
 GXPBASE = '${@os.path.normpath("${LAYERDIR}/")}'