Revert "wait for IPv6 RA if using none/static IPv6 assignment"
    
    This reverts commit c603419030136570b5944dc4620f62d07b9e82bb.
    
    wait_for_ipv6_dad_link is only called from dhclient script,
    so the original intent "wait for IPv6 RA if using none/static IPv6 assignment"
    does not seem to be correct.
    
    Anyway, this brings an issue on isolated networks, where you don't
    have any routes outside. dhclient-script hangs on this check
    and after it times out, dhclient is able to set the address normally.
    
    (cherry picked from commit 76f6566fd777e0ee20416061ecb795e8daef33e1)
    
    Resolves: #1795276
    
    patch_name: 0066.patch
    present_in_specfile: true
    location_in_specfile: 66
    squash_commits: true