add listen events for win32 only after accept mutex is hold

src/event/ngx_event.c

diff --git a/src/event/ngx_event.c b/src/event/ngx_event.c
index 8d18ef6..e30c563 100644
--- a/src/event/ngx_event.c
+++ b/src/event/ngx_event.c
@@ -776,6 +776,10 @@
 
             rev->handler = ngx_event_acceptex;
 
+            if (ngx_use_accept_mutex) {
+                continue;
+            }
+
             if (ngx_add_event(rev, 0, NGX_IOCP_ACCEPT) == NGX_ERROR) {
                 return NGX_ERROR;
             }
@@ -792,6 +796,10 @@
         } else {
             rev->handler = ngx_event_accept;
 
+            if (ngx_use_accept_mutex) {
+                continue;
+            }
+
             if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
                 return NGX_ERROR;
             }