FindOpenSSL: Detect OpenSSL 3.0.0
The OpenSSL versioning is changing with the upcoming 3.0.0 release. https://www.openssl.org/blog/blog/2018/11/28/version/ Since 3.0.0, the patch letters are being dropped. The new format is: MAJOR.MINOR.PATCH
The OPENSSL_VERSION variable can now be directly derived from the new OPENSSL_VERSION_STR macro. https://www.openssl.org/docs/manmaster/man3/OPENSSL_VERSION_NUMBER.html
Backport: release
Edited by Brad King