Add "microcom" to pending.

Add "microcom" to pending.

Our device bringup folks wanted a simple serial console, both on the
host and on the device. This is certainly enough to replace what I've
been using personally on the host.

I'd never heard of "microcom" until I asked the internets what busybox
users use, so I don't care what we call this or what the options are
called. (But would like to decide before it gets ossified in a million
factory test scripts and the like!)

The tool that this replaces for me defaulted to /dev/ttyUSB0, but since
I don't know whether that default would be useful for most other people
too, I left that out. Command-line history will solve my transition
problem.