update LAYERSERIES_COMPAT

Signed-off-by: Max Ihlenfeldt <max@igalia.com>

Author: MaxIhlenfeldt

meta-chromium/conf/layer.conf

@@ -9,6 +9,6 @@ BBFILE_PATTERN_chromium-browser-layer := "^${LAYERDIR}/"
 BBFILE_PRIORITY_chromium-browser-layer = "7"
 
 LAYERVERSION_chromium-browser-layer = "1"
-LAYERSERIES_COMPAT_chromium-browser-layer = "dunfell gatesgarth hardknott honister kirkstone langdale mickledore nanbield"
+LAYERSERIES_COMPAT_chromium-browser-layer = "kirkstone langdale mickledore nanbield"
 
 LAYERDEPENDS_chromium-browser-layer = "clang-layer core openembedded-layer"