depmodwrapper-cross: add config directory option

Native depmod by default try to find config files from the following
directories:
```
${STAGING_ETCDIR_NATIVE}/depmod.d
/run/depmod.d
/usr/local/lib/depmod.d
/lib/depmod.d
```

but none of them is correct, change to load config files from
${sysconfdir}/depmod.d of basedir.

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Signed-off-by: Ming Liu <liu.ming50@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit aa03d77f)
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>