USB: usbfs: fix potential infoleak in devio

The stack object “ci” has a total size of 8 bytes. Its last 3 bytes
are padding bytes which are not initialized and leaked to userland
via “copy_to_user”.

Git-commit: 681fef8380eb818c0b845fca5d2ab1dcbab114ee
Git-repo: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git


Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dennis Cagle <d-cagle@codeaurora.org>
(cherry picked from commit 681fef8380eb818c0b845fca5d2ab1dcbab114ee)
Change-Id: Idacb2d5ed64654f85fb86fcce0a196223a7ac2af