fsync under win32

The latest fsync patch broke win32 build. There's no fsync under win32,
so the #define fsync(fd) _commit(fd) which was removed from port/win32.h
in version 1.45 is still necessary.

Regards,
Andreas
Index: win32.h
===================================================================
RCS file: /projects/cvsroot/pgsql/src/include/port/win32.h,v
retrieving revision 1.45
diff -u -r1.45 win32.h
--- win32.h    20 May 2005 14:53:26 -0000    1.45
+++ win32.h    16 Jun 2005 13:43:50 -0000
@@ -19,6 +19,7 @@
 #define HAVE_FSYNC_WRITETHROUGH
 #define HAVE_FSYNC_WRITETHROUGH_ONLY
 #define ftruncate(a,b)    chsize(a,b)
+#define fsync(fd) _commit(fd)

 #define USES_WINSOCK