Add TDX Attestation

[yogeshbdeshpande]

rendered at https://github.com/veraison/docs/blob/intel-tdx-musings/musings/intel-tdx-attestation.md

[setrofim]

Real nice write-up, just a few minor nits. In addition to the comments on specific lines -- there appear to be a few lines (mainly in the glossary, but also a few elsewhere) that aren't wrapped to the same column width as the rest of the document.

[THS-on]

@yogeshbdeshpande @jraman567 how does it align with the latest discussions we had a month back? Any plans on updating it?

[jraman567]

Hi @yogeshbdeshpande , thanks for point me to this doc. I'll review this shortly.

I'm unsure if I followed-up with you, but I'm currently blocked on the TDX implementation due to the following issue. We need a scheme to store the reference of the TD measurements in CoRIM. Are you aware of one, if so could you please point me to it? Thank you!