[DCCP]: Fix typo

This fixes a small typo in net/dccp/libs/packet_history.c

Signed off by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dccp/ccids/lib/packet_history.c

 /*
- *  net/dccp/packet_history.h
+ *  net/dccp/packet_history.c
  *
  *  Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
  *