This fixes when configuring with --without-default-devices:

  $ qemu-system-mips64el -bios /dev/null -M fulong2e
  qemu-system-mips64el: Unknown device 'ati-vga' for bus 'PCI'
  Aborted (core dumped)

  (gdb) bt
  #0  0x00007ffff5a2753f in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
  #1  0x00007ffff5a11895 in __GI_abort () at abort.c:79
  #2  0x00005555558768d3 in qdev_create (bus=bus@entry=0x5555562664b0, name=name@entry=0x555555b24efb "ati-vga") at hw/core/qdev.c:131
  #3  0x00005555558d15e1 in pci_create_multifunction (bus=bus@entry=0x5555562664b0, devfn=devfn@entry=-1, multifunction=multifunction@entry=false, name=name@entry=0x555555b24efb "ati-vga") at hw/pci/pci.c:2104
  #4  0x00005555558d1a7a in pci_create (bus=bus@entry=0x5555562664b0, devfn=devfn@entry=-1, name=name@entry=0x555555b24efb "ati-vga") at hw/pci/pci.c:2121
  #5  0x0000555555763081 in mips_fulong2e_init (machine=<optimized out>) at hw/mips/mips_fulong2e.c:352
  #6  0x000055555587e23b in machine_run_board_init (machine=0x5555560b2000) at hw/core/machine.c:1030
  #7  0x00005555556cbea2 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4463

And then:

  $ qemu-system-mips64el -bios /dev/null -M fulong2e
  qemu-system-mips64el: Unsupported NIC model: rtl8139

Fixes: 862b4a29 and 7c28b925
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190316200818.8265-8-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>