[DCCP] CCID2: Initial CCID2 (TCP-Like) implementation

Original work by Andrea Bittau, Arnaldo Melo cleaned up and fixed several
issues on the merge process.

For now CCID2 was turned the default for all SOCK_DCCP connections, but this
will be remedied soon with the merge of the feature negotiation code.

Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dccp/Kconfig

@@ -24,6 +24,10 @@ config INET_DCCP_DIAG
 	def_tristate y if (IP_DCCP = y && INET_DIAG = y)
 	def_tristate m
 
+config IP_DCCP_ACKVEC
+	depends on IP_DCCP
+	def_bool N
+
 source "net/dccp/ccids/Kconfig"
 
 menu "DCCP Kernel Hacking"