add Packet provider links to the root README.md

Author: displague

cluster-autoscaler/README.md

@@ -17,6 +17,7 @@ You should also take a look at the notes and "gotchas" for your specific cloud p
 * [AWS](./cloudprovider/aws/README.md)
 * [BaiduCloud](./cloudprovider/baiducloud/README.md)
 * [HuaweiCloud](./cloudprovider/huaweicloud/README.md)
+* [Packet](./cloudprovider/packet/README.md#notes) 
 
 # Releases
 
@@ -144,3 +145,4 @@ Supported cloud providers:
 * OpenStack Magnum https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/cloudprovider/magnum/README.md
 * DigitalOcean https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/cloudprovider/digitalocean/README.md
 * Exoscale https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/cloudprovider/exoscale/README.md
+* Packet https://github.com/kubernetes/autoscaler/blob/master/cluster-autoscaler/cloudprovider/packet/README.md