ipvs: remove extra lookups for ICMP packets

 	Remove code that should not be called anymore.
Now when ip_vs_out handles replies for local clients at
LOCAL_IN hook we do not need to call conn_out_get and
handle_response_icmp from ip_vs_in_icmp* because such
lookups were already performed for the ICMP packet and no
connection was found.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>