lang/rust: Update to 1.34.2

• While here add patches from [1] for LibreSSL 2.9.1 support

[1] https://github.com/sfackler/rust-openssl/pull/1097

Changes: https://blog.rust-lang.org/2019/05/13/Security-advisory.html
Changes: https://blog.rust-lang.org/2019/05/14/Rust-1.34.2.html
PR: 237495 [1]
Security: 37528379-76a8-11e9-a4fd-00012e582166