Do not reduce Tile_ID==9999999 data

[ndrory]

From a recent clarifying email by Evelyn:

I just checked the logs for MJD 60645 where we have the strange 9999999 tiles. That was the night of the highway blackout, where we took a series of exposures at roughly the same altitude and azimuth before, during and after the blackout to measure the effects on the sky background. So they are nothing to do with LVM but it was agreed that they might be useful additional data for the team investigating the effect of the light pollution from the highway.