ipv4: remove ip_rt_dump from route.c

ip_rt_dump do nothing after IPv4 route caches removal, so we can remove it.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc include/net/route.h
Simple merge

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

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