iommu: Pass struct iommu_iotlb_gather to ->unmap() and ->iotlb_sync()

To allow IOMMU drivers to batch up TLB flushing operations and postpone
them until ->iotlb_sync() is called, extend the prototypes for the
->unmap() and ->iotlb_sync() IOMMU ops callbacks to take a pointer to
the current iommu_iotlb_gather structure.

All affected IOMMU drivers are updated, but there should be no
functional change since the extra parameter is ignored for now.

Signed-off-by: Will Deacon <will@kernel.org>

drivers/iommu/msm_iommu.c

@@ -509,7 +509,7 @@ static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova,
 }
 
 static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
-			      size_t len)
+			      size_t len, struct iommu_iotlb_gather *gather)
 {
 	struct msm_priv *priv = to_msm_priv(domain);
 	unsigned long flags;