openssl: avoid segfault during running tests on Ubuntu trusty

Import the commit 6693a549d673 ("test/test_pkey_ec: do not use dummy 0
order", 2017-02-03) from upstream. Hopefully this will fix the segfault
on RubyCI icc16-x64:

  http://rubyci.org/logs/rubyci.s3.amazonaws.com/icc-x64/ruby-trunk/log/20170301T050002Z.fail.html.gz

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57750 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/openssl/test_pkey_ec.rb

@@ -282,7 +282,7 @@ class OpenSSL::TestEC < OpenSSL::PKeyTestCase
       group = OpenSSL::PKey::EC::Group.new(:GFp, 17, 2, 2)
       group.point_conversion_form = :uncompressed
       gen = OpenSSL::PKey::EC::Point.new(group, OpenSSL::BN.new("040501", 16))
-      group.set_generator(gen, 0, 0)
+      group.set_generator(gen, 19, 1)
 
       # 3 * (6, 3) = (16, 13)
       point_a = OpenSSL::PKey::EC::Point.new(group, OpenSSL::BN.new("040603", 16))