[GH-575] Added Deprecated warning in channel make-private cmd

[ChandanChainani]

Fixes #575

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[ChandanChainani]

/check-cla

[isacikgoz]

Hey @ChandanChainani you need to run make docks to generate newly added documentation to the commands. That will fix the CI issue.

[isacikgoz]

Thank you @ChandanChainani awesome!