devel/cargo: Add patch to fix LibreSSL support

Cargo crashes when compiled with LibreSSL. To fix this, it needs newer
versions of some crates it depends on. See the following GitHub pull
request:
https://github.com/rust-lang/cargo/pull/3521

The registry is also recreated because of those new crates.

PORTREVISION is bumped to 2.

PR: 216431
Reported by: NHO (#freebsd-ports IRC channel)
Tested by: NHO, matthew@reztek.cz, Ben Woods
Approved by: antoine (mentor)
Differential Revision: https://reviews.freebsd.org/D9327