sock/ssl: free SSL on socket close()

Fixes #2684

Change-Id: I0a91e7a70c53c8130921c70872b28d199d862346
Signed-off-by: Boris Glimcher <Boris.Glimcher@emc.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/14432
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot

module/sock/posix/posix.c

@@ -1084,6 +1084,8 @@ posix_sock_close(struct spdk_sock *_sock)
 	 * memory. */
 	close(sock->fd);
 
+	SSL_free(sock->ssl);
+
 	spdk_pipe_destroy(sock->recv_pipe);
 	free(sock->recv_buf);
 	free(sock);