Make code less ugly

From: Michael Prokop <mprokop@sipwise.com>

ngcp-update-db-schema

@@ -70,7 +70,9 @@ if ! mysql -usipwise -p${SIPWISE_DB_PASSWORD} ngcp -e 'describe db_schema'  >/de
 fi
 
 running_on_active_node() {
-  if [ -x /usr/sbin/ngcp-check_active ] ; then
+  if ! [ -x /usr/sbin/ngcp-check_active ] ; then
+    return 1
+  else
     if /usr/sbin/ngcp-check_active -q ; then
       verbose "This seems to be the active node, nothing to do."
       return 0
@@ -78,8 +80,6 @@ running_on_active_node() {
       verbose "This seems to be the inactive node, applying revisions."
       return 1
     fi
-  else
-      return 1
   fi
 }