use cf->cycle->new_log because at merge stage cf->pool->log is old log

src/mail/ngx_mail_core_module.c

diff --git a/src/mail/ngx_mail_core_module.c b/src/mail/ngx_mail_core_module.c
index 3af9fbf..15627d2 100644
--- a/src/mail/ngx_mail_core_module.c
+++ b/src/mail/ngx_mail_core_module.c
@@ -437,7 +437,7 @@
         return NGX_CONF_ERROR;
     }
 
-    cscf->resolver = ngx_resolver_create(cf->pool, &u.addrs[0]);
+    cscf->resolver = ngx_resolver_create(cf, &u.addrs[0]);
     if (cscf->resolver == NULL) {
         return NGX_CONF_OK;
     }