x86/Documentation: Update the contact email for L3 cache index disable functionality

The mailing list discuss@x86-64.org is now defunct.
Use the lkml in its place.
Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Greg KH <greg@kroah.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-api@vger.kernel.org
Cc: sboyd@codeaurora.org
Cc: sudeep.holla@arm.com
Link: http://lkml.kernel.org/r/1431125098-9470-1-git-send-email-Aravind.Gopalakrishnan@amd.com
Link: http://lkml.kernel.org/r/1431936437-25286-2-git-send-email-bp@alien8.de
[ Changed the contact email to lkml. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Documentation/ABI/testing/sysfs-devices-system-cpu

@@ -162,7 +162,7 @@ Description:	Discover CPUs in the same CPU frequency coordination domain
 What:		/sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
 Date:		August 2008
 KernelVersion:	2.6.27
-Contact:	discuss@x86-64.org
+Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
 Description:	Disable L3 cache indices
 
 		These files exist in every CPU's cache/index3 directory. Each