#23391: simplify setting fallback (missing in the squash commit)

core/src/main/java/org/elasticsearch/common/settings/Setting.java

@@ -376,12 +376,12 @@ public class Setting<T> extends ToXContentToBytes {
         if (exists(primary)) {
             return get(primary);
         }
-        if (fallbackSetting == null) {
-            return exists(secondary) ? get(secondary) : get(primary);
-        }
         if (exists(secondary)) {
             return get(secondary);
         }
+        if (fallbackSetting == null) {
+            return get(primary);
+        }
         if (fallbackSetting.exists(primary)) {
             return fallbackSetting.get(primary);
         }