Remove AIX support again

[silverwind]

See silverwind/default-gateway#10. In summary, I had a os-locked optional native dependency to support AIX but it turns out npm has a bug where it will ignore os in some cases, leading to gyp error spam on commands like npm ci and npm install --force.

Dropped the platform again for this reason until someone provides a pure-js implementation. Ideally, this should be released as semver-major.

[sindresorhus]

I don't use os in any packages. It's buggy and I don't want to prevent a consumer of this package to support different platforms just because they depend on internal-ip. Runtime checks are better with optionalDependencies is a better choice.

But it doesn't matter. default-gateway has os, so this package doesn't need it anyway.

[silverwind]

Okay, os removed.

[silverwind]

Went ahead and removed os in default-gateway too. It's better that way because there is no issue with installing on unsupported platforms like AIX. It will allow dependants to gracefully treat the thrown Unsupported Platform error which is better than failing the installation entirely.

[sindresorhus]

Will this require a major release of internal-ip?

[silverwind]

It is breaking only for AIX users which should represent like 0.00001% of the users (if any at all). Your decision.