ACPI: EC: Accelerate query execution

ACPI: EC: Accelerate query execution

commit a62e8f1978f49e52f87a711ff6711b323d4b12ff upstream.

Split EC query handling into acknowledge and execution phase.
This allows much smaller pending query lattency and lowers chances
of EC going "wild" and losing events.

Reference: http://bugzilla.kernel.org/show_bug.cgi?id=14858

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: François Valenduc <francois.valenduc@tvcablenet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>