postgres-xc: Fix for Linuxbrew. (#128)
postgres-xc: Fix for Linuxbrew. (#128)

postgres-xc was trying to build with Bonjour. Also, it was missing a few
dependencies.

Closes Linuxbrew/homebrew-core#127.
Linuxbrew/homebrew-core,rwhogg/homebrew-core,Linuxbrew/homebrew-core,maxim-belkin/homebrew-core,rwhogg/homebrew-core,LinuxbrewTestBot/homebrew-core,LinuxbrewTestBot/homebrew-core,maxim-belkin/homebrew-core