Build documentation has outdated links

[Araneidae]

The build dependencies in the Build Instructions are outdated and links to an unavailable location.

It would probably be best to simply redirect users to the Releases page and point out that the appropriate deps zip has the required files. Just so long as this is truthful!

[Araneidae]

@EmilioPeJu, for your interest.

[Araneidae]

Some notes from PR #63 for discussion:

• First of all, what do we (or other users) do when any of the tar file sources is unavailable? This does happen: links change, sites move, or even sometime sites go offline temporarily or even permanently. This is why I have always urged for a curated collection of definitive copies of the tar files (and this is why the MD5 sums are always checked).
• Secondly, the user needs to be advised that there are now two targets available (zynq and zynqmp, I think). These need to be mentioned in the documentation.
• Thirdly, the list of MD5 sums in the document is good ... but it's a headache to maintain, and I can see already that it is out of date, it doesn't match the list of files being downloaded by the referenced script.
• Finally, I see that we do generate a sensible looking collection of assets in the Releases page. How is this generated? This should definitely be referenced.

I agree with the maintenance of tar-files.sh, but there needs to be a fallback (the very last two lines explain why...) and this file needs to be easy to maintain.

[tomtrafford]

I think it will be worth noting that the tar files should also be contained in the developer container - looking through the rootfs documentation it doesn't look like the container gets referred to once, despite its dockerfile being located in the repo and the rootfs CI creating and publishing it - Later this week I will try to write some documentation on this and the above.