arm64: select ACPI PCI code only when both features are enabled

ACPI and PCI are no longer coupled to each other. Specify requirements
for both when pulling in code.

Signed-off-by: Sinan Kaya <okaya@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>