If ip link says the interface is up but mii-tool says it's got no link before
negotiation is complete, ifup fails very quickly.  In 8.0, we used to wait 5
seconds between ip set up and running mii-tool, which was enough for my epic100
card to negotiate the link.  In Phoebe, it always fails, because there's a 1-2
second window between ip link reporting the interface is up and mii-tool getting
a `link ok'.  The patch I'm going to attach restores the 8.0 behavior, in that
it takes at most 5 seconds to bail out, but it gives more time for mii-tool to
return a success result.