Description of problem:
`oadm manage-node --evacuate` will show "Flag --evacuate has been deprecated, use 'oadm manage-node drain NODE' instead", but `oadm manage-node drain` doesn't work and it's not in oadm manage-node -h

Version-Release number of selected component (if applicable):
oc/oadm v3.4.0.34+87d9d8d

How reproducible:
Always

Steps to Reproduce:
1. # oadm manage-node <node> --evacuate --dry-run
Flag --evacuate has been deprecated, use 'oadm manage-node drain NODE' instead

Listing matched pods on node: <node>

NAME                            READY     STATUS      RESTARTS   AGE
...

2. # oadm manage-node drain <node> --dry-run
error: must provide a node operation. Supported operations: --schedulable, --evacuate and --list-pods
See 'oadm manage-node -h' for help and examples.

3. # oadm manage-node -h

Actual results:
1. Succeed to run, but it indicate user to use "drain"
2. Failed to run with "drain"
3. There is no "drain"

Expected results:
Since "drain" does not work and it's not in help info, should drop the message for "drain".
If need to use "drain", then it's a functional error.

Additional info:

The proper syntax is `oadm drain` not `oadm manage-node drain`.

PR: https://github.com/openshift/origin/pull/12226

Per convo with mfojtik, this is not a blocker.  Removing from 3.4.