ACPI: add a Kconfig option for ACPI procfs interface

Add a kconfig option CONFIG_ACPI_PROCFS to make procfs interface
a configurable attribute of ACPI.

No procfs interface is actually deprecated,
and no sysfs interface is added in this patch.

CONGI_ACPI_PROCFS is used to mark procfs interface as deprecated
once the same function is duplicated in sysfs.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>