[llvm] [llvm][release] Add links to automatically built packages on release page (PR #147021)

[David Spickett via llvm-commits]

DavidSpickett wrote:

I went through some of the most popular projects on GitHub and most of them sidestep this by having very few packages, or their GitHub release is just a source archive and you get binaries elsewhere.

I did find https://github.com/rustdesk/rustdesk/releases/tag/1.4.0# which does a similar thing using a table, but I found a list easier to navigate, and a table would have large gaps if we listed all of our major packages.

"I am a user who has a <mac/linux> machine powered by <architecture> and I want to download llvm" is the use case here.

https://github.com/llvm/llvm-project/pull/147021