Don't allocate aperture when swiotlb is enabled and no AGP found

Noone needs it then

Signed-off-by: Andi Kleen <ak@suse.de>

Index: linux/arch/x86_64/kernel/aperture.c
===================================================================
--- linux.orig/arch/x86_64/kernel/aperture.c
+++ linux/arch/x86_64/kernel/aperture.c
@@ -245,6 +245,8 @@ void __init iommu_hole_init(void) 
 		
 	if (aper_alloc) { 
 		/* Got the aperture from the AGP bridge */
+	} else if (swiotlb && !valid_agp) { 
+		/* Do nothing */
 	} else if ((!no_iommu && end_pfn >= 0xffffffff>>PAGE_SHIFT) ||
 		   force_iommu ||
 		   valid_agp ||