compatibility issues with olders gcc: unnamed union members cannot be used in init

This solves compilation in olders gcc due a unresolved bug in <gcc-4.6 that unnamed union members cannot be used in initializer (stupid win-hat developers, always later)

Theres no fun in a cheap software that relies on to high dependences, due high dependences need modern hardware.. an modern hardware dont need memory savings: so please commit thi for possibility to have compton in many distros that already not have gcc 4.6+.