LXC cleanup deep indentation in lxcDomainSetAutostart

* src/lxc/lxc_driver.c: refactor lxcDomainSetAutostart() to avoid deep
  indentation of the code

src/lxc/lxc_driver.c

@@ -1992,10 +1992,18 @@ static int lxcDomainSetAutostart(virDomainPtr dom,
 
     autostart = (autostart != 0);
 
-    if (vm->autostart != autostart) {
-        if ((configFile = virDomainConfigFile(dom->conn, driver->configDir, vm->def->name)) == NULL)
+    if (vm->autostart == autostart) {
+        ret = 0;
         goto cleanup;
-        if ((autostartLink = virDomainConfigFile(dom->conn, driver->autostartDir, vm->def->name)) == NULL)
+    }
+
+    configFile = virDomainConfigFile(dom->conn, driver->configDir,
+                                     vm->def->name);
+    if (configFile == NULL)
+        goto cleanup;
+    autostartLink = virDomainConfigFile(dom->conn, driver->autostartDir,
+                                        vm->def->name);
+    if (autostartLink == NULL)
         goto cleanup;
 
     if (autostart) {
@@ -2024,7 +2032,6 @@ static int lxcDomainSetAutostart(virDomainPtr dom,
     }
 
     vm->autostart = autostart;
-    }
     ret = 0;
 
 cleanup: