parsnp: Depends on zlib for Linuxbrew
parsnp: Depends on zlib for Linuxbrew

Use the brewed zlib rather than the host's.

Closes #6057.

Signed-off-by: Shaun Jackman <b580dab3251a9622aba3803114310c23fdb42900@gmail.com>

pditommaso/homebrew-science,heuermh/homebrew-science,andrewjpage/homebrew-science