Automatic merge from submit-queue

azure: loadbalancer rules use DSR

**What this PR does / why we need it**:
Enables "direct server return" on the load balancer in Azure, which causes the DIP to be preserved when traffic goes through the load balancer. This enables service traffic to go to the Service Port rather than having to go through the NodePort.

**Special notes for your reviewer**:
N/A.

**Tested with...**:
```shell
kubectl run nginx --image=nginx
kubectl run nginx2 --image=nginx
kubectl expose deployment nginx --port=80 --type=LoadBalancer
kubectl expose deployment nginx2 --port=80 --type=LoadBalancer
```
Ensuring that both services got external IPs and that the resources created looked correct.

**Release note**:
```release-note
azure: load balancer preserves destination ip address
```

CC: @brendandburns