i386/pc: add piix and q35 machtypes to sorting families for -M \?

With this patch applied, the output of -M \? is

> Supported machines are:
> pc                   Standard PC (i440FX + PIIX, 1996) (alias of pc-i440fx-2.2)
> pc-i440fx-2.2        Standard PC (i440FX + PIIX, 1996) (default)
> pc-i440fx-2.1        Standard PC (i440FX + PIIX, 1996)
> pc-i440fx-2.0        Standard PC (i440FX + PIIX, 1996)
> pc-i440fx-1.7        Standard PC (i440FX + PIIX, 1996)
> pc-i440fx-1.6        Standard PC (i440FX + PIIX, 1996)
> pc-i440fx-1.5        Standard PC (i440FX + PIIX, 1996)
> pc-i440fx-1.4        Standard PC (i440FX + PIIX, 1996)
> pc-1.3               Standard PC (i440FX + PIIX, 1996)
> pc-1.2               Standard PC (i440FX + PIIX, 1996)
> pc-1.1               Standard PC (i440FX + PIIX, 1996)
> pc-1.0               Standard PC (i440FX + PIIX, 1996)
> pc-0.15              Standard PC (i440FX + PIIX, 1996)
> pc-0.14              Standard PC (i440FX + PIIX, 1996)
> pc-0.13              Standard PC (i440FX + PIIX, 1996)
> pc-0.12              Standard PC (i440FX + PIIX, 1996)
> pc-0.11              Standard PC (i440FX + PIIX, 1996)
> pc-0.10              Standard PC (i440FX + PIIX, 1996)
> q35                  Standard PC (Q35 + ICH9, 2009) (alias of pc-q35-2.2)
> pc-q35-2.2           Standard PC (Q35 + ICH9, 2009)
> pc-q35-2.1           Standard PC (Q35 + ICH9, 2009)
> pc-q35-2.0           Standard PC (Q35 + ICH9, 2009)
> pc-q35-1.7           Standard PC (Q35 + ICH9, 2009)
> pc-q35-1.6           Standard PC (Q35 + ICH9, 2009)
> pc-q35-1.5           Standard PC (Q35 + ICH9, 2009)
> pc-q35-1.4           Standard PC (Q35 + ICH9, 2009)
> isapc                ISA-only PC
> none                 empty machine

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1145042


Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>