install krb5-workstation only when manage_krb_config is true

[bp85]

Hi,

Is it possible to update the install.pp to do a check whether to install the krb5-workstation package depending on the manage_krb5_config variable.
Right now we don't want to manage krb5 config via realmd, but since there's a package installtion, we're getting duplicate resources.
I'm happy to open a PR, if it makes any sense

Bhanu

[walkamongus]

yes -- PRs welcome!