ioctl: register LTTng ioctl

The LTTng 2.0 kernel tracer (stand-alone module package, available at
http://lttng.org) uses the 0xF6 ioctl range for tracer control and
transport operations.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/ioctl/ioctl-number.txt

@@ -319,4 +319,6 @@ Code  Seq#(hex)	Include File		Comments
 					<mailto:thomas@winischhofer.net>
 0xF4	00-1F	video/mbxfb.h		mbxfb
 					<mailto:raph@8d.com>
+0xF6	all	LTTng			Linux Trace Toolkit Next Generation
+					<mailto:mathieu.desnoyers@efficios.com>
 0xFD	all	linux/dm-ioctl.h