Thanks for the report.
In debian-installer it looks like micro-evtd does indeed exit
immediately on startup, as you said. But /dev/ttyS1 is there, and
surprisingly, microapl commands seem to work.
Unfortunately I'm having trouble getting any further right now, because
the 4.8 and 4.6 kernels both don't detect the hard drive! The stable
kernel is fine with it, so that looks like a regression that I'll have
to track down first... installing a toolchain in d-i is not an exercise
I'm particularly interested in!