ghc: Fix libtinfo detection for Linuxbrew
ghc: Fix libtinfo detection for Linuxbrew

Closes #1421.

Signed-off-by: Estelle Poulin <34c6fceca75e456f25e7e99531e2425c6c1de443@inspiredby.es>
LinuxbrewTestBot/homebrew-core,rwhogg/homebrew-core,LinuxbrewTestBot/homebrew-core,maxim-belkin/homebrew-core,maxim-belkin/homebrew-core,Linuxbrew/homebrew-core,rwhogg/homebrew-core,Linuxbrew/homebrew-core