[babl/wip/msvc] babl/babl-util.c: Use _WIN32, not __WIN32__

[Chun-wei Fan <fanchunwei src gnome org>]

commit 7c494b408bf3a010080f960c94d26878cbd8f5f4
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Mon Jan 20 16:15:40 2020 +0800

    babl/babl-util.c: Use _WIN32, not __WIN32__
    
    __WIN32__ is MinGW-only, but _WIN32 works for both MinGW and Visual Studio

 babl/babl-util.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/babl/babl-util.c b/babl/babl-util.c
index cab9ab1d9..e7842f9a8 100644
--- a/babl/babl-util.c
+++ b/babl/babl-util.c
@@ -20,14 +20,14 @@
 #include <math.h>
 #include "babl-internal.h"
 
-#ifdef __WIN32__
+#ifdef _WIN32
 #include <windows.h>
 #else
 #include <sys/time.h>
 #include <time.h>
 #endif
 
-#ifdef __WIN32__
+#ifdef _WIN32
 static LARGE_INTEGER start_time;
 static LARGE_INTEGER timer_freq;