iommu/vt-d: Remove some pointless to_pci_dev() calls

Mostly made redundant by using dev_name() instead of pci_name(), and one
instance of using *dev->dma_mask instead of pdev->dma_mask.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --cc drivers/iommu/intel-iommu.c
Simple merge