Enable configurable log file for cloud-node-manager when running as a Windows service

[jrvaldes]

What would you like to be added:

azure-cloud-node-manager lacks of configurable option for log file location.

Why is this needed:

This feature is critical when running the azure-cloud-node-manager as a Windows service in a Windows host. That is:

azure-cloud-node-manager.exe --windows-service

The flag to adjust the log verbosity (--v) is present, but is practically unusable with the Windows service use case, given there is no visility of the logs.

For example:

azure-cloud-node-manager.exe --windows-service --v=5 ---log-file=C:\var\log\cloud-node-manager\cloud-node-manager.log

where --log-file set the path of the file to store the logs in the Windows host.

References:

cloud-provider-azure/cmd/cloud-node-manager/app/options/options.go

Line 125 in 6bc7669

fs := fss.FlagSet("misc")

[jrvaldes]

/cc @marosset @jsturtevant