staging: kpc2000: added designated initializers to two structs.

Fixed the following two sparse warnings by using designated
initializers:

  drivers/staging/kpc2000/kpc2000/cell_probe.c:101:34: warning: Using plain integer as NULL pointer
  drivers/staging/kpc2000/kpc2000/cell_probe.c:364:34: warning: Using plain integer as NULL pointer

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>