script: include-what-you-use header check

script: include-what-you-use header check

The tool proposed;

script.c should add these lines:

script.c should remove these lines:
- #include <sys/file.h>  // lines 53-53
- #include <sys/types.h>  // lines 48-48
- #include "c.h"  // lines 61-61

and the change nearly did what the tool told. We should keep on
using c.h, not err.h. The config.h is not needed, it's added
automaticly.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>