patch #4459: Fix for rpm package builds
* avrdude.spec.in: update the RPM spec file:
- Default to enable-doc=yes during configure.
- Move info file to docs package.
- Make building of docs package conditional. Basic
idea copied from avr-gcc.
git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk@558 81a1dc3b-b13d-400b-aceb-764788c761c2