Replaced the remaining NGX_OLD_THREADS check with NGX_WIN32.

src/event/ngx_event.c

diff --git a/src/event/ngx_event.c b/src/event/ngx_event.c
index 31514c4..69b69ff 100644
--- a/src/event/ngx_event.c
+++ b/src/event/ngx_event.c
@@ -212,7 +212,9 @@
         timer = ngx_event_find_timer();
         flags = NGX_UPDATE_TIME;
 
-#if (NGX_OLD_THREADS)
+#if (NGX_WIN32)
+
+        /* handle signals from master in case of network inactivity */
 
         if (timer == NGX_TIMER_INFINITE || timer > 500) {
             timer = 500;

src/os/win32/ngx_win32_config.h

diff --git a/src/os/win32/ngx_win32_config.h b/src/os/win32/ngx_win32_config.h
index f4b2eea..36a486f 100644
--- a/src/os/win32/ngx_win32_config.h
+++ b/src/os/win32/ngx_win32_config.h
@@ -218,8 +218,6 @@
 #define NGX_HAVE_LITTLE_ENDIAN  1
 #define NGX_HAVE_NONALIGNED     1
 
-#define NGX_OLD_THREADS         1
-
 
 #define NGX_WIN_NT        200000