PM: documentation cleanups

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

Documentation/kernel-parameters.txt

@@ -147,8 +147,10 @@ and is between 256 and 4096 characters. It is defined in the file
 			default: 0
 
 	acpi_sleep=	[HW,ACPI] Sleep options
-			Format: { s3_bios, s3_mode }
-			See Documentation/power/video.txt
+			Format: { s3_bios, s3_mode, s3_beep }
+			See Documentation/power/video.txt for s3_bios and s3_mode.
+			s3_beep is for debugging; it makes the PC's speaker beep
+			as soon as the kernel's real-mode entry point is called.
 
 	acpi_sci=	[HW,ACPI] ACPI System Control Interrupt trigger mode
 			Format: { level | edge | high | low }