test/openssl: Support OpenSSL 1.1.1

	OpenSSL 1.1.1 rejects some shorter keys, which caused some failures of
	`make test-all TESTS=openssl`.

	https://rubyci.org/logs/rubyci.s3.amazonaws.com/debian/ruby-master/log/20190606T003005Z.fail.html.gz

	This change merges 6bbc31ddd1 and 63fb3a36d1 in
	https://github.com/ruby/openssl.
	Reference: https://github.com/ruby/openssl/pull/217

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_6@67735 b2dd03c8-39d4-4d8f-98ff-823fe69b080e