Add LM feature for X86

[mscdex]

This is useful in easily determining 32-bit vs. 64-bit.

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[mscdex]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

As with my previous PR, I'm unable to sign the CLA because the CLA signing site does not allow choosing of which email address to use. I don't care about attribution or anything anyway.