hw/pci-host/pnv_phb: Avoid quitting QEMU if hotplug of pnv-phb-root-port fails

hw/pci-host/pnv_phb: Avoid quitting QEMU if hotplug of pnv-phb-root-port fails

Currently QEMU terminates if you try to hotplug pnv-phb-root-port in
an environment where it is not supported, e.g. if doing this:

 echo "device_add pnv-phb-root-port" | \
 ./qemu-system-ppc64 -monitor stdio -M powernv9

To avoid this problem, the pnv_phb_root_port_realize() function should
not use error_fatal when trying to set the properties which might not
be available.

Fixes: c2f3f78af5 ("ppc/pnv: set root port chassis and slot using Bus properties")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20221109122210.115667-1-thuth@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>