pc-q35-7.2 breaks the pcie hot plugin
Description of problem:
the new pc-q35 version >6.0 break the pcie hot plug feature
if I use 5.2, 6.0, it works fine. `dmesg | grep pcieport` shows that:
there is pciehp which provide functionality of hot plug for PCIE device
```
[test@localhost ~]$ dmesg | grep pcieport
[    1.161129] pcieport 0000:00:02.0: PME: Signaling with IRQ 24
[    1.162254] pcieport 0000:00:02.0: AER: enabled with IRQ 24
[    1.163218] pcieport 0000:00:02.0: pciehp: Slot #0 AttnBtn+ PwrCtrl+ MRL- AttnInd+ PwrInd+ HotPlug+ Surprise+ Interlock+ NoCompl- IbPresDis- LLActRep+
```

if I switch to 6.1, 6.2, 7.0, 7.1 ,7.2, the pciehp does not show any control slot.
```
[test@localhost ~]$ dmesg | grep pcieport
[    1.164311] pcieport 0000:00:02.0: PME: Signaling with IRQ 24
[    1.165446] pcieport 0000:00:02.0: AER: enabled with IRQ 24
```
Steps to reproduce:
1. run the qemu command as I produced
2. connect to console
3. run `dmesg | grep pcieport`
4. you can try to plug in a GPU or something else, the device initialization will fail because there is no pciehp slow to power it on, normall you will see something like following, with >6.0 you cannot see them:
  ```
  pciehp: Slot(0-8): Attention button pressed
  pciehp: Slot(0-8) Powering on due to button press
  pciehp: Slot(0-8): Card present
  pciehp: Slot(0-8): Link Up
  ```
Additional information: