[DCCP] timewait: Remove leftover extern declarations

Gerrit Renker noticed dccp_tw_deschedule and submitted a patch with a FIXME,
but as he suggests in the same patch the best thing is to just ditch this
declaration, while doing that also noticed that tcp_tw_count is as well not
defined anywhere, so ditch it too.
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

net/dccp/dccp.h

@@ -35,8 +35,6 @@ extern int dccp_debug;
 extern struct inet_hashinfo dccp_hashinfo;
 
 extern atomic_t dccp_orphan_count;
-extern int dccp_tw_count;
-extern void dccp_tw_deschedule(struct inet_timewait_sock *tw);
 
 extern void dccp_time_wait(struct sock *sk, int state, int timeo);