ACPI: allow drivers to request both device and system notify events

System notify events (0x00-0x7f) are common across all device types
and should be handled in Linux/ACPI, not in drivers.  However, some
BIOSes use system notify events in device-specific ways that require
the driver to be involved.

This patch adds a ACPI_DRIVER_ALL_NOTIFY_EVENTS driver flag.  When a
driver sets this flag and supplies a .notify method, Linux/ACPI calls
the .notify method for ALL notify events on the device, not just the
device-specific (0x80-0xff) events.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>