Use GenerateName while generating machine-resource names

[hardikdr]

What would you like to be added: MCM has been computing the name of the machine-resources so far, it would probably be a good idea to use the generateName feature, and let the API-server decide the name.

• We should check the side-effects of this change, both in terms of gardener and MCM, and how KCM is doing it yet, and if there is a good reason to move or not move.

cc @amshuman-kr

[elankath]

• [x] Names are already generated in function GetMachineFromTemplate in controller_utils.go
• [ ] For MachineSet objects, we currently use the object name: Name: d.Name + "-" + encodedMachineTemplateSpecHash in getNewMachineSet in deployment_sync.go . We can change to using generateName with the prefix as the deployment name.