iommu/amd: Prevent binding other PCI drivers to IOMMU PCI devices

AMD IOMMU driver makes use of IOMMU PCI devices, so prevent binding other
PCI drivers to IOMMU PCI devices.

This fixes a bug reported by Boris that system suspend/resume gets broken
on AMD platforms. For more information, please refer to:
	https://lkml.org/lkml/2015/9/26/89

Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd_iommu_init.c

@@ -1256,6 +1256,9 @@ static int iommu_init_pci(struct amd_iommu *iommu)
 	if (!iommu->dev)
 		return -ENODEV;
 
+	/* Prevent binding other PCI device drivers to IOMMU devices */
+	iommu->dev->match_driver = false;
+
 	pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET,
 			      &iommu->cap);
 	pci_read_config_dword(iommu->dev, cap_ptr + MMIO_RANGE_OFFSET,