[PATCH] openpromfs: remove unnecessary casts

Remove unnecessary casts in fs/openpromfs/inode.c

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>