[llvm] [LangRef] Document accessing memory outside of object is UB. (PR #128429)

[Nikita Popov via llvm-commits]

nikic wrote:

> This removes the sentence regarding loading values up to the !align does not trap. My reading of that sentence implies that alignment would imply dereferenceability, but it is not clear if that's only intended for the !align metadata.

This bit is referring to the `align` attribute, not the `!align` metadata. I do agree that we should drop this, see https://github.com/llvm/llvm-project/issues/90446.

https://github.com/llvm/llvm-project/pull/128429