dscp: Apply TOS config to both ipv4 and ipv6 when network is v6
dscp: Apply TOS config to both ipv4 and ipv6 when network is v6

When a network is using v6, it may still receive v4 connections.

Change-Id: I8b77a557a13cde9ee0d1bbb78e1935bb050de310

aristanetworks/goarista,aristanetworks/goarista