Fix firewall ingress ipv6

[majst01]

Description

If Ingress rules with IPv6 in the TO filed exists, the following error is thrown:

panic: exit status 1: /etc/metal/networker/nftrules_673841649:36:20-35: Error: Could not resolve hostname: Address family for hostname not supported
                ip daddr { 2001:db8:0:113::/64 } ip6 saddr 2001:db8::1/128 tcp dport { 22 } counter accept comment "allow incoming ssh"
                           ^^^^^^^^^^^^^^^^


goroutine 1 [running]:
github.com/metal-stack/metal-networker/pkg/netconf.mustApply({0xb16780, 0xc0003a6ba0}, {0xc0003bc000, 0x1742}, {0xc00037a720, 0x27}, {0xa1baca, 0x13}, 0x1)
        github.com/metal-stack/[email protected]/pkg/netconf/configurator.go:282 +0x27f
github.com/metal-stack/metal-networker/pkg/netconf.applyAndCleanUp(0xc0002833c0, {0xb16780, 0xc0003a6ba0}, {0xa17f90, 0xc}, {0xc00037a720, 0x27}, {0xa1baca, 0x13}, 0x180, ...)
        github.com/metal-stack/[email protected]/pkg/netconf/configurator.go:256 +0x1e9
github.com/metal-stack/metal-networker/pkg/netconf.firewallConfigurator.ConfigureNftables({{{{0xc0002632b8, 0x2}, {0xc000010fa8, 0x3, 0x3}, {0xc000026c90, 0x24}, {0xc000144300, 0x2dd}, {0xc000263770, ...}, ...}, ...}, ...}, ...)
        github.com/metal-stack/[email protected]/pkg/netconf/configurator.go:162 +0x125
github.com/metal-stack/metal-networker/pkg/netconf.firewallConfigurator.Configure({{{{0xc0002632b8, 0x2}, {0xc000010fa8, 0x3, 0x3}, {0xc000026c90, 0x24}, {0xc000144300, 0x2dd}, {0xc000263770, ...}, ...}, ...}, ...}, ...)
        github.com/metal-stack/[email protected]/pkg/netconf/configurator.go:108 +0xc8
main.(*installer).configureNetwork(0xc00022fe18)
        github.com/metal-stack/metal-images/cmd/install.go:415 +0x1ee
main.(*installer).do(0xc00022fe18)
        github.com/metal-stack/metal-images/cmd/install.go:84 +0x2d6