iommu/ipmmu-vmsa: Prepare to handle 40-bit error addresses

On R-Car Gen3, the faulting virtual address is a 40-bit address, and
comprised of two registers.  Read the upper address part, and combine
both parts, when running on a 64-bit system.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>