autotools: show error and stop ./configure when cannot find po4a-translate
autotools: show error and stop ./configure when cannot find po4a-translate

gnunn1/terminix,gnunn1/tilix,dsboger/tilix,gnunn1/terminix,gnunn1/tilix,phw/terminix,gnunn1/tilix,dsboger/tilix,phw/terminix