[autotools,bugfix] Feed include path of all modules to dune-autogen

Previously only the include path of the local modules were used. This
caused errors with installed dune-common modules, similar to:

--> aclocal...

Error: Could not find dune-common/am!
Usage: dune-autogen DUNE_MODULE_PATH_LIST [options]
  --ac=, --acversion=VERSION   use a specific VERSION of autoconf
  --am=, --amversion=VERSION   use a specific VERSION of automake
  -h,    --help                you already found this :-)
--- Failed to build dune-typetree ---
Terminating dunecontrol due to previous errors!

This is also related to https://dune-project.org/flyspray/index.php?do=details&task_id=891

With this patch we include the aclocal, m4 or am directory of all modules
(installed and local ones) and everything works again as exspected.