* ext/openssl/ossl_ssl.c: Disabled OpenSSL::SSL::SSLSocket if
  defined(OPENSSL_NO_SOCK).

  This fixes a linkage error on platforms which do not have socket.
  OpenSSL itself is still useful as a set of cryptographic functions
  even on such platforms.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40680 b2dd03c8-39d4-4d8f-98ff-823fe69b080e