treematch/km_partitioning.c #include "config.h",
but there is no such file when the embedded treematch is used.
In order to prevent the embedded treematch from incorrectly using
the config.h from the embedded hwloc, generate a dummy config.h.
Signed-off-by: Gilles Gouaillardet <gilles@rist.or.jp>
(cherry picked from commit 0aeb27f77650d3ee97e17e770c9e5aa487d5e1f5)