Fix null pointer dereference in ssl_module_init

CLA: Trivial

Reviewed-by: Paul Yang <yang.yang@baishancloud.com>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8183)

(cherry picked from commit 758229f7d22775d7547e3b3b886b7f6a289c6897)