Bug#1094879: gnustep-gui FTCBFS: configures for the build architecture during dh_auto_clean

[Yavor Doganov]

Yavor Doganov wrote:
> I'll just make another try with the official package in unstable,
> obtained with apt-get source.

FYI, the result is the same with gnustep-gui/0.31.1-8: a successful
build.  I'm not attaching the log as it's basically the same.