Revert "PCI: PM: Do not read power state in pci_enable_device_flags()"

Revert commit 4514d991

 ("PCI: PM: Do not read power state in
pci_enable_device_flags()") that is reported to cause PCI device
initialization issues on some systems.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=213481
Link: https://lore.kernel.org/linux-acpi/YNDoGICcg0V8HhpQ@eldamar.lan
Reported-by: Michael <phyre@rogers.com>
Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Fixes: 4514d991

 ("PCI: PM: Do not read power state in pci_enable_device_flags()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>