`self.settings` vs `self.info.settings` in `validate`/`validate_build`

right now, documentation is inconsistent, e.g.:
https://docs.conan.io/en/latest/reference/conanfile/methods.html#validate
https://docs.conan.io/en/latest/reference/conanfile/methods.html#validate-build
use just `self.settings`, while:
https://docs.conan.io/en/latest/creating_packages/define_abi_compatibility.html
uses `self.info.settings`.
for newcomers, it's not clear, which one should be used and in that circumstances.
I think documentation should be aligned with the same recommendation on all pages.
if for some reason, both `self.info.settings` and plain `self.settings` could be used, it should have some disclaimer, describing the difference between them.
see also https://github.com/conan-io/conan-center-index/pull/13754