Documentation: document debugpat commandline option

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index b3a5aad..681d615 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -571,6 +571,8 @@
 
 	debug_objects	[KNL] Enable object debugging
 
+	debugpat	[X86] Enable PAT debugging
+
 	decnet.addr=	[HW,NET]
 			Format: <area>[,<node>]
 			See also Documentation/networking/decnet.txt.