Remove unneeded (and undesirable) casts.

Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Chris Kennedy <c@groovy.org>
Cc: Kevin Thayer <nufan_wfk@yahoo.com>
Cc: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>