Use the "real" NULL value, don't try to be cute and define your own
value for something that the compiler obviously supports.
Cc: Johnny Kim <johnny.kim@atmel.com> Cc: Rachel Kim <rachel.kim@atmel.com> Cc: Dean Lee <dean.lee@atmel.com> Cc: Chris Park <chris.park@atmel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>