[DCCP] ackvec: Ditch dccpav_buf_len

Simplifying the code a bit as we're always using DCCP_MAX_ACKVEC_LEN.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc net/dccp/ackvec.c
Simple merge

diff --cc net/dccp/ackvec.h
Simple merge

diff --cc net/dccp/ipv4.c
Simple merge

diff --cc net/dccp/minisocks.c
Simple merge