Recognize armv8l [ci skip]
Recognize armv8l [ci skip]

Addresses https://github.com/randombit/botan/issues/1543
randombit/botan,randombit/botan,webmaster128/botan,randombit/botan,webmaster128/botan,webmaster128/botan,webmaster128/botan,webmaster128/botan,randombit/botan,randombit/botan