Replace Stream#forEach() with Collection#forEach()

Change-Id: I2b261c3d91d345907b165bd61eb7b6c45011c247
diff --git a/apps/openstacknetworking/routing/src/main/java/org/onosproject/openstacknetworking/routing/OpenstackFloatingIpManager.java b/apps/openstacknetworking/routing/src/main/java/org/onosproject/openstacknetworking/routing/OpenstackFloatingIpManager.java
index 1de2455..bd12b5b 100644
--- a/apps/openstacknetworking/routing/src/main/java/org/onosproject/openstacknetworking/routing/OpenstackFloatingIpManager.java
+++ b/apps/openstacknetworking/routing/src/main/java/org/onosproject/openstacknetworking/routing/OpenstackFloatingIpManager.java
@@ -231,7 +231,7 @@
         sIncomingBuilder.matchEthType(Ethernet.TYPE_IPV4)
                 .matchIPDst(floatingIp.toIpPrefix());
 
-        gatewayService.getGatewayDeviceIds().stream().forEach(deviceId -> {
+        gatewayService.getGatewayDeviceIds().forEach(deviceId -> {
             TrafficSelector.Builder sForTrafficFromVmBuilder = DefaultTrafficSelector.builder()
                     .matchEthType(Ethernet.TYPE_IPV4)
                     .matchIPDst(floatingIp.toIpPrefix())
@@ -278,8 +278,8 @@
                 .matchIPDst(floatingIp.toIpPrefix())
                 .build();
 
-        gatewayService.getGatewayDeviceIds().stream().forEach(gnodeId -> {
-            TrafficTreatment treatmentForTrafficFromExternal =  DefaultTrafficTreatment.builder()
+        gatewayService.getGatewayDeviceIds().forEach(gnodeId -> {
+            TrafficTreatment treatmentForTrafficFromExternal = DefaultTrafficTreatment.builder()
                     .setEthSrc(Constants.DEFAULT_GATEWAY_MAC)
                     .setEthDst(associatedVm.mac())
                     .setIpDst(associatedVm.ipAddresses().stream().findFirst().get())
@@ -336,7 +336,7 @@
                 .matchIPSrc(associatedVm.ipAddresses().stream().findFirst().get().toIpPrefix())
                 .build();
 
-        gatewayService.getGatewayDeviceIds().stream().forEach(gnodeId -> {
+        gatewayService.getGatewayDeviceIds().forEach(gnodeId -> {
             TrafficTreatment treatment = DefaultTrafficTreatment.builder()
                     .setIpSrc(floatingIp)
                     .setEthSrc(Constants.DEFAULT_GATEWAY_MAC)