libressl: bump to version 2.8.2
See release notes since 2.7.4 at
https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.8.0-relnotes.txt
https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.8.1-relnotes.txt
https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.8.2-relnotes.txt
Signed-off-by: Carlos Santos <casantos@datacom.com.br>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>