* ext/openssl/openssl_missing.h, ext/openssl/ossl.h: Remove
unnecessary 'extern "C"' blocks. We don't use C++ and these headers
are local to ext/openssl, so there is no need to enclose with it.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55161 b2dd03c8-39d4-4d8f-98ff-823fe69b080e