acpid: drop x86 architecture dependency

acpid: drop x86 architecture dependency

Closes #11241

While ACPI is historically exclusively a x86 feature, ia64 and (some) arm64
server platforms also use it.  Furthermore, even if the firmware does not
provide an ACPI interface and/or the kernel is not built with ACPI support,
acpid can still be used to command an orderly shutdown of the system as it
also listens for KEY_POWER / KEY_SUSPEND events from the input subsystem
(and calls shutdown by default).

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>