CVE-2022-49196 powerpc/pseries: Fix use after free in remove_phb_dynamic()

In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries: Fix use after free in removephbdynamic In removephbdynamic we use &phb-ioresource, after we've called deviceunregister&hostbridge-dev. But the unregister may have freed phb, because pcibiosfreecontrollerdeferred ...