Add debug tracing support during certain AML method execution.

Four more module parameters are created under /sys/module/acpi/parameters/:
trace_method_name:	the AML method name that user wants to trace

trace_debug_layer:	the temporary debug_layer used when tracing the method.
			Using 0xffffffff by default if it is 0.

trace_debug_level:	the temporary debug_level used when tracing the method.
			Using 0x00ffffff by default if it is 0.

trace_state:		The status of the tracing feature.
			"enabled" means this feature is enabled
			and the AML method is traced every time it's executed.
			"1" means this feature is enabled and the AML method
			will only be traced during the next execution.
			"disabled" means this feature is disabled.
			Users can enable/disable this debug tracing feature by
			"echo string > /sys/module/acpi/parameters/trace_state".
			"string" should be one of "enable", "disable" and "1".

http://bugzilla.kernel.org/show_bug.cgi?id=6629Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>