Merge pull request #10976 from yuwata/typesafe-netlink-call

netlink: introduce typesafe netlink functions

diff --cc src/network/networkd-link.c
Simple merge

diff --cc src/network/networkd-manager.c
Simple merge

diff --cc src/network/networkd-route.c
Simple merge

diff --cc src/network/networkd-routing-policy-rule.c
Simple merge

diff --cc src/network/networkd-routing-policy-rule.h
Simple merge