hw/pci-host/prep: Correct RAVEN bus bridge memory region size

hw/pci-host/prep: Correct RAVEN bus bridge memory region size

memory_region_set_size() handle the 16 Exabytes limit by
special-casing the UINT64_MAX value. This is not a problem
for the 32-bit maximum, 4 GiB.
By using the UINT32_MAX value, the bm-raven MemoryRegion
ends up missing 1 byte:

  $ qemu-system-ppc -M prep -S -monitor stdio -usb
  memory-region: bm-raven
    0000000000000000-00000000fffffffe (prio 0, i/o): bm-raven
      0000000000000000-000000003effffff (prio 0, i/o): alias bm-pci-memory @pci-memory 0000000000000000-000000003effffff
      0000000080000000-00000000ffffffff (prio 0, i/o): alias bm-system @system 0000000000000000-000000007fffffff

Fix by using the correct value. We now have:

  memory-region: bm-raven
    0000000000000000-00000000ffffffff (prio 0, i/o): bm-raven
      0000000000000000-000000003effffff (prio 0, i/o): alias bm-pci-memory @pci-memory 0000000000000000-000000003effffff
      0000000080000000-00000000ffffffff (prio 0, i/o): alias bm-system @system 0000000000000000-000000007fffffff

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200601142930.29408-3-f4bug@amsat.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>