The default maximum transmit length for NCM USB frames should be so
that a short packet happens at the end if the device supports a length
greater than the defined maximum. This is achieved by adding 4 bytes
to the maximum length so that the existing logic can fit a short
packet there.
Signed-off-by: Hans Petter Selasky <hselasky@c2i.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>