Add orchestration priority for galera upgrade

Change-Id: I82b417f02b1afb833970c31e0fe8db9f5872a3c1
Related-prod: PROD-29630
diff --git a/galera/meta/salt.yml b/galera/meta/salt.yml
index 15ebaf4..bff3d2f 100644
--- a/galera/meta/salt.yml
+++ b/galera/meta/salt.yml
@@ -3,4 +3,8 @@
     priority: 140
   slave:
     priority: 150
-
+orchestration:
+  upgrade:
+    applications:
+      galera:
+        priority: 910