d2i_SSL_SESSION() was changed in 0.9.7f

src/event/ngx_event_openssl.c

diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
index ba83e7f..7d61dfe 100644
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -1353,7 +1353,7 @@
 ngx_ssl_get_cached_session(ngx_ssl_conn_t *ssl_conn, u_char *id, int len,
     int *copy)
 {
-#if OPENSSL_VERSION_NUMBER >= 0x00908000
+#if OPENSSL_VERSION_NUMBER >= 0x0090707fL
     const
 #endif
     u_char                   *p;