Add ebtables filters from the legacy firmware

package/gluon-ebtables-filter-multicast/Makefile

...filter-multicast/files/lib/gluon/ebtables/100-mcast-chain

...er-multicast/files/lib/gluon/ebtables/110-mcast-allow-arp

...-multicast/files/lib/gluon/ebtables/110-mcast-allow-babel

...-multicast/files/lib/gluon/ebtables/110-mcast-allow-btlpd

...multicast/files/lib/gluon/ebtables/110-mcast-allow-dhcpv4

...multicast/files/lib/gluon/ebtables/110-mcast-allow-dhcpv6

...r-multicast/files/lib/gluon/ebtables/110-mcast-allow-icmp

...multicast/files/lib/gluon/ebtables/110-mcast-allow-icmpv6

...r-multicast/files/lib/gluon/ebtables/110-mcast-allow-igmp

...r-multicast/files/lib/gluon/ebtables/110-mcast-allow-ospf

...ables-filter-multicast/files/lib/gluon/ebtables/300-mcast

package/gluon-ebtables-filter-ra-dhcp/Makefile

...es-filter-ra-dhcp/files/lib/gluon/ebtables/200-dir-dhcpv4

...es-filter-ra-dhcp/files/lib/gluon/ebtables/200-dir-dhcpv6

...bles-filter-ra-dhcp/files/lib/gluon/ebtables/200-dir-radv

package/gluon-ebtables/files/lib/gluon/ebtables/.keep

...age/gluon-ebtables/files/lib/gluon/ebtables/100-dir-chain

...age/gluon-ebtables/files/lib/gluon/ebtables/101-dir-rules