This reverts commit 15ede265.

Apparently, the old code was based on libjpeg6. However, most systems use
libjpeg8 now, which has a few new features like cropping, leading to a lot
of fuckup with feh on libjpeg8 systems. Now feh works with libjpeg8,
but probably doesn't support libjpeg6 anymore.

Also, this code copypasta really sucks :-)

feh -O should also be able to run without it, but that requires slightly more work.
I'll fix that one later, I guess.

<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=373209>