[TCP]: Let TCP_CONG_ADVANCED default to n

It doesn't seem to make much sense to let an "If unsure, say N." option 
default to y.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/Kconfig

@@ -448,7 +448,6 @@ config IP_TCPDIAG_IPV6
 config TCP_CONG_ADVANCED
 	bool "TCP: advanced congestion control"
 	depends on INET
-	default y
 	---help---
 	  Support for selection of various TCP congestion control
 	  modules.