The FACS may still exist when the reduced hardware flag is set in FADT;
it is optional. Since it contains the hardware signature field which
indicates that a hibernated system should boot cleanly instead of
attempting to resume, a platform may choose to expose it. Propagate it
correctly.
Also avoid a NULL pointer dereference if the platform doesn't provide
a DSDT.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <881dd0a2558ecbdfa02c844722d8a1103ab97ab3.camel@infradead.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
[lersek@redhat.com: uncrustify]