Update arch/ to use sg helpers

arch/alpha/kernel/pci_iommu.c

arch/arm/common/dmabounce.c

arch/blackfin/kernel/dma-mapping.c

arch/ia64/hp/common/sba_iommu.c

arch/ia64/hp/sim/simscsi.c

arch/ia64/sn/pci/pci_dma.c

arch/m68k/kernel/dma.c

arch/mips/mm/dma-default.c

arch/powerpc/kernel/dma_64.c

arch/powerpc/kernel/ibmebus.c

arch/powerpc/kernel/iommu.c

arch/powerpc/platforms/ps3/system-bus.c

arch/sparc/kernel/ioport.c

arch/sparc/mm/io-unit.c

arch/sparc/mm/iommu.c

arch/sparc/mm/sun4c.c

arch/sparc64/kernel/iommu.c

arch/sparc64/kernel/iommu_common.c

arch/sparc64/kernel/ldc.c

arch/sparc64/kernel/pci_sun4v.c