Initialize domain flags to 0

It's random number after the domain is allocated by kmem_cache_alloc

Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 213a5c8..65aa1d4 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1180,6 +1180,7 @@
 	set_bit(num, iommu->domain_ids);
 	domain->id = num;
 	domain->iommu = iommu;
+	domain->flags = 0;
 	iommu->domains[num] = domain;
 	spin_unlock_irqrestore(&iommu->lock, flags);