[PATCH] module: fix mod_sysfs_setup() return value

mod_sysfs_setup() doesn't return error when kobject_add_dir() failed.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>