cmd part of this struct is the same as an index of itself within
_ioctls[]. In fact this cmd is unused, so we can drop this part.

Link: http://lkml.kernel.org/r/20160831033414.9910.66697.stgit@pluto.themaw.netSigned-off-by: NTomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: NIan Kent <raven@themaw.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>