asset: set the advertise address based on pod ip

[aaronlevy]

This flag was removed in #151, but looks like we do still need this in some cases.

The bootkube-apiserver was setting the correct endpoint record for the default kubernetes service (kubectl get endpoint/kubernetes). However, after bootkube exits, the self-hosted api-server will eventually overwrite the endpoint again -- and it was using the host's default interface, which is not routable in some cases (e.g. virtualbox).

There may be some other options here (e.g. why does bootkube apiserver use correct interface, but hostNetwork api-server pod does not) -- but going to revert this part of the change so we avoid the regression until we have a better option.

/cc @dghubble @Quentin-M @bassam

[bassam]

@aaronlevy this does not fix the problem I'm seeing but might still be necessary due to the virtualbox default interface not being routable.

I made some progress tracking down the issue I'm seeing and it does not happen when I revert #247. I created a new issue for tracking #258

[derekparker]

Definitely seems to be a larger issue here, but this patch LGTM as a fix for now.

[dghubble]

This may mean coreos-baremetal needs to use a fork again :(

[aaronlevy]

@dghubble there may be other options here - but it is a regression, so need to fix in the short term.