In APEI firmware first mode, hardware error is reported by hardware to
firmware firstly, then firmware reports the error to Linux in a GHES
error record via POLL/SCI/IRQ/NMI etc.

This may result in some issues if OS has no full APEI support.  So
some firmware implementation will work in a back-compatible mode by
default.  Where firmware will only notify OS in old-fashion, without
GHES record.  For example, for a fatal hardware error, only NMI is
signaled, no GHES record.

To gain full APEI power on these machines, APEI bit in generic _OSC
call can be specified to tell firmware that Linux has full APEI
support.  This patch adds the APEI bit support in generic _OSC call.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>