bug#720: Patch to fix CVS Emacs compilation error on Windows XP SP2.

[Eli Zaretskii]

> Cc: 720@emacsbugs.donarmstrong.com, bug-gnu-emacs@gnu.org,
>         Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Thu, 14 Aug 2008 16:15:04 -0400
> From: Francis Litterio <flitterio@gmail.com>
> 
>       w32.c(3820) : error C2520: conversion from unsigned __int64 to double 
> not implemented, use signed __int64

"Not implemented"?  I'm not sure we want to support such a deficient
compiler.  How about this:

  DWORD tot_hi = memstex.ullTotalPhys >> 32;
  DWORD tot_md = (memstex.ullTotalPhys & 0x00000000ffffffffLL) >> 10;
  DWORD tot_lo = memstex.ullTotalPhys % 1024LL;
  totphys = tot_hi * 4194304.0 + tot_md + tot_lo / 1024.0;

Does this work?