The paths in doxygen.conf assumed that srcdir=builddir and broke
otherwise. Use autoconf to fill in the paths to the srcdir so that the
files can be found when users have a separate build directory (as with
distcheck).
Signed-off-by: Dan Nicholson <dbn.lists@gmail.com>
Tested-by: Cyril Brulebois <kibi@debian.org>
Reviewed-by: Gaetan Nadon <memsize@videotron.ca>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>