Provide a more information early_data message in s_server

s_server reported early_data not being sent and early_data being
rejected in the same way, i.e. "No early data received". This is
slightly misleading so this commit provides a different error message
if the early data is rejected.

Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4738)