htslib: Fix include directory path for zlib
htslib: Fix include directory path for zlib

Fixes a build break in htslib

[git-p4: depot-paths = "//sw/gpgpu/nvbio/main/": change = 18878505]

NVlabs/nvbio,NVlabs/nvbio,NVlabs/nvbio,kimrutherford/nvbio,kimrutherford/nvbio,kimrutherford/nvbio,kimrutherford/nvbio,NVlabs/nvbio