security/libressl: Update to 2.2.2

• Bump SHLIB versions of libssl/crypto/tls
• Bump OPENSSL_SHLIBVER in bsd.openssl.mk
• Add UPDATING entry for SHLIB version bump
• Narrow scope of CONFLICTS (portlint)

Changes:

ftp://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.2.2-relnotes.txt

Differential_revision: D3278
Reviewed by: koobs (mentor), vsevolod (maintainer, mentor)
Approved by: koobs (mentor)