proposal: x/crypto/ssh: support service names in Client.Dial with net.LookupPort

[HouseK]

Add support for service names additional to port numbers to ssh.Client.Dial.

PR: https://go.dev/cl/443775 (golang/crypto#235)

net.Dial already supports this same, this proposal adds that same feature to ssh.Client.Dial.

Currently ssh.Client.Dial uses strconv.ParseUint to convert a port number as string into the int type it needs.
The proposal is to use net.LookupPort instead.

net.LookupPort is purpose build for interpreting strings as ports and has the additional feature that it also supports service names.

[drakkan]

This addition seems reasonable to me

cc @golang/proposal-review

[seankhliao]

With no api change I don't think this requires a proposal

[hanwen]

I have already approved the change, and didn't think this needs a proposal at all.

[dr2chase]

It needs the proposal tag, I was about to ok a CL after the "is this what it claims" Google-required supply-chain check, and realized that it might reach the "proposal" bar, pinged the rest of the release team, and consensus was "yes".

[HouseK]

Thanks for all the input! What would be the next step now?