defect 3190944: touch /etc/xCATSN in mypostscript when installing SN

git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@8946 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

xCAT-server/lib/perl/xCAT/Postage.pm

@@ -629,6 +629,12 @@ sub makescript
             }
         }
     }
+
+    # touch the /etc/xCATSN when it is a service node
+    if (xCAT::Utils->isSN($node)) {
+        push @scriptd, "touch /etc/xCATSN";
+    }
+
     ###Please do not remove or modify this line of code!!! xcatdsklspost depends on it
     push @scriptd, "# postscripts-start-here\n";