xtrabackup added to pkg and git formulas

Change-Id: Idf4bf4774fe2df081446bd0498fe16c968395e17
diff --git a/salt/master/formula/pkg/saltstack.yml b/salt/master/formula/pkg/saltstack.yml
index eeff26b..e4a4c1c 100644
--- a/salt/master/formula/pkg/saltstack.yml
+++ b/salt/master/formula/pkg/saltstack.yml
@@ -37,3 +37,6 @@
             sphinx:
               source: pkg
               name: salt-formula-sphinx
+            xtrabackup:
+              source: pkg
+              name: salt-formula-xtrabackup