pkg-config complains about missing qt-mt.pc

[Marko Anastasov <marko marko anastasov name>]

This is not a serious blocking issue, however I'd still like
to have it resolved:

$ pkg-config --list-all
...
Package qt-mt was not found in the pkg-config search path.
Perhaps you should add the directory containing `qt-mt.pc'
to the PKG_CONFIG_PATH environment variable
Package 'qt-mt', required by 'avahi-qt3', not found

I searched and realized that qt-mt.pc definitely doesn't exist
on my computer, and AFAIK it shouldn't.

Marko