iommu/io-pgtable: Add helper functions for TLB ops

Add some simple wrappers to avoid having the guts of the TLB operations
spilled all over the page table implementations, and to provide a point
to implement extra common functionality.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 8c615b7..876f6a7 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -75,6 +75,6 @@
 		return;
 
 	iop = container_of(ops, struct io_pgtable, ops);
-	iop->cfg.tlb->tlb_flush_all(iop->cookie);
+	io_pgtable_tlb_flush_all(iop);
 	io_pgtable_init_table[iop->fmt]->free(iop);
 }