ipv6: Don't pass net to ip6_route_info_append().

net is not used in ip6_route_info_append() after commit 36f19d5b
("net/ipv6: Remove extra call to ip6_convert_metrics for multipath case").

Let's remove the argument.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-10-kuniyu@amazon.com


Signed-off-by: Paolo Abeni <pabeni@redhat.com>