iommu/io-pgtable-arm: Convert to IOMMU API TLB sync

Now that the core API issues its own post-unmap TLB sync call, push that
operation out from the io-pgtable-arm internals into the users. For now,
we leave the invalidation implicit in the unmap operation, since none of
the current users would benefit much from any change to that.

Change-Id: Ida17fdcb050e9f7d7b952bd9709159342b8a46e7
CC: Magnus Damm <damm+renesas@opensource.se>
CC: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Git-commit: 32b124492bdf974f68eaef1bde80dc8058aef002
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


[guptap: fix downstream support]
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>