Cherry-pick htslib#1258
Cherry-pick htslib#1258

Cherry-pick htslib commit 515f6df8f7f7 ("Remove compressBound
assertions. (PR #1258)").

This fixes compressBound() assertions when running bedtools testsuite
on an IBM Z machine with hardware-accelerated zlib.

arq5x/bedtools2,arq5x/bedtools2,arq5x/bedtools2,arq5x/bedtools2,arq5x/bedtools2