May need to set pio settings for lilac history output

I'm not sure whether this needs to be fixed, but in looking quickly at how LILAC's PIO settings are specified (for files output by LILAC itself, not files output by CTSM), it looks like the PIO settings may never be specified explicitly for LILAC (at least, I don't see an equivalent of `lnd_modelio.nml` for lilac). Instead, I see this:

https://github.com/ESCOMP/CTSM/blob/2abb3f4a0f477cd0243f032fc625434af8907189/lilac/src/lilac_io.F90#L106-L116

So it seems to me like lilac may be using the pio settings from another component (ctsm? but I'm not sure if that's guaranteed to be the case, particularly if the host atmosphere uses pio for its own purposes). I'm thinking we may need to fix this long-term. One problem that could possibly arise from the current setup is if CTSM is running on a subset of the atmosphere processors.

@mvertens feel free to weigh in here if you understand this better than me, since I think you put in place the initial pio-related code in lilac.