Don't depend on i2d_X509_EXTENSIONS
Don't depend on i2d_X509_EXTENSIONS(), which didn't exist on CentOS 5,
to copy extensions from a request to a certificate. Instead, use logic
from Tomas Mraz's patch to just iterate through them and call
X509_add_req().
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>