Update README.md

Author: andyzhangx

README.md

@@ -52,6 +52,7 @@ follow guide [here](./docs/install-driver-on-aks.md)
  - [Shared Disk](./deploy/example/sharedisk)
  - [Volume Limits](./deploy/example/volumelimits)
  - [fsGroupPolicy](./deploy/example/fsgroup)
+ - [Tune disk performance on Linux](./docs/enhancements/feat-add-ability-to-tune-azuredisk-performance-parameters.md)
 
 ### Troubleshooting
  - [CSI driver troubleshooting guide](./docs/csi-debug.md)