Merge remote-tracking branch 'remotes/mcayland/qemu-sparc' into staging

Merge remote-tracking branch 'remotes/mcayland/qemu-sparc' into staging

* remotes/mcayland/qemu-sparc:
  apb: implement IOMMU translation for PCI host bridge
  apb: handle reading/writing of IOMMU control registers
  apb: fix IOMMU register sizes
  apb: Move IOMMU registers into a separate IOMMUState struct
  tcx: move initialisation from realizefn to initfn
  tcx: move initialisation from SysBusDevice class to TCX class realizefn
  cg3: add extra check to prevent CG3 register array overflow
  cg3: move initialisation from realizefn to initfn

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>