PCI/ACPI: Move _OSC query checks to separate function

Move the checks about whether the _OSC controls are requested from the
firmware to a separate function.

Link: https://lore.kernel.org/r/20210824122054.29481-4-joro@8bytes.org


Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>