Trim out-of-bounds sequences in pvdiv_table_topsnps()

[Alice-MacQueen]

In pvdiv_table_topsnps(), want to reduce the number of instances of this warning/message when range > 0:

In valid.GenomicRanges.seqinfo(x, suggest.trim = TRUE) : GRanges object contains 30431 out-of-bound ranges located on sequences X, Y, and Z. Note that ranges located on a sequence whose length is unknown (NA) or on a circular sequence are not considered out-of-bound (use seqlengths() and isCircular() to get the lengths and circularity flags of the underlying sequences). You can use trim() to trim these ranges. See ?trim,GenomicRanges-method for more information.