Add aarch64-unknown-netbsd target#53165

Merged

bors merged 3 commits intorust-lang:masterfrom

jakllsch:netbsd-ad22a005-b917-47f3-8156-f717d36f6bbe

Aug 13, 2018

Commits on Aug 6, 2018

NetBSD: fix signedess of char
jakllsch
committed

Commits on Aug 7, 2018

Add aarch64-unknown-netbsd target
jakllsch
committed

Commits on Aug 10, 2018

aarch64-unknown-netbsd: add openssl configuration
jakllsch
committed