security/botan3: update to 3.7.1 release (+)

While here, install manpage as botan3.1 to avoid conflicts with botan2 package

Release notes: https://botan.randombit.net/news.html#version-3-7-0-2025-02-04 \

		https://botan.randombit.net/news.html#version-3-7-1-2025-02-05