x86: mmconf enable mcfg early

Patch
	"x86: validate against ACPI motherboard resources"

changed the mmconf init sequence, and init MMCONF late in acpi_init.

here change it back to old sequence:

 1. check hostbridge in early
 2. check MCFG with e820 in early
 3. if all fail, will check MCFg with acpi _CRS in acpi_init

So we can make MCONF working again when acpi=off is set if hostbridge
support that.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>