[FEATURE] Add more comprehensive support for ssh_config, specifically bastion hosts

[memetb]

System Information

Linux distribution debian

Terraform version v1.1.3

Provider and libvirt versions 9adc2521e37b0c8938330bf81111d3c633825c76-dirty

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Hello @dmacvicar, I've coded a new feature for the project and am opening an issue prior to submitting a WIP PR.

I have updated the code for ssh.go to add more thorough support for making use of ssh_config parameters.

This code change resolves the following specific and important issues:

• inability to use a identity file other than ~/.ssh/id_rsa
• inability to use bastion hosts as they are defined in the ssh_config file

This feature requires upgrading ssh_config module to v1.2.0 which is the as of now current module (is currently at v0.0.0 in the master branch). Other than this, all changes are confined to ssh.go.

[SimonWoidig]

This is something that we would love to see aswell - especially the proxies.

[memetb]

@SimonWoidig : fyi, this feature is completed in #1059, and merged to production branch on memetb/terraform-provider-libvirt fork project. You will have to build on your own though.