x86: Fix S3 resume after creating an HVM guest.

If we don't use PIT, we should disable it at boot time and at S3
resuming. In Xen this is done by disable_pit_irq(), but this function
is used by __initcall(). After bootstrap it will be discarded and may be
overwritten. This usually results in S3 resuming failure.

Signed-off-by: Huacai Chen <huacai.chen@intel.com>
Signed-off-by: Li Zhang <li.zhang@intel.com>

     1.1 --- a/xen/arch/x86/time.c	Mon Jun 09 09:47:51 2008 +0100
     1.2 +++ b/xen/arch/x86/time.c	Mon Jun 09 09:51:14 2008 +0100
     1.3 @@ -999,7 +999,7 @@ void __init early_time_init(void)
     1.4      setup_irq(0, &irq0);
     1.5  }
     1.6  
     1.7 -static int __init disable_pit_irq(void)
     1.8 +static int disable_pit_irq(void)
     1.9  {
    1.10      if ( !using_pit && cpu_has_apic )
    1.11      {