net: remove outdated comment for ipv4 and ipv6 protocol handler

since f9242b6b28d61295f2bf7e8adfb1060b382e5381
inet: Sanitize inet{,6} protocol demux.

there are not pretended hash tables for ipv4 or
ipv6 protocol handler.

Signed-off-by: Baker Zhang <Baker.kernel@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

diff --cc net/ipv6/protocol.c
Simple merge