lftp: Depends on zlib [Linux]
lftp: Depends on zlib [Linux]

Fix configure: error: cannot find -lz library, install zlib-devel package

Closes Linuxbrew/homebrew-core#9167.

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

maxim-belkin/homebrew-core,maxim-belkin/homebrew-core,Linuxbrew/homebrew-core,rwhogg/homebrew-core,LinuxbrewTestBot/homebrew-core,LinuxbrewTestBot/homebrew-core,Linuxbrew/homebrew-core,rwhogg/homebrew-core