We no longer need to include headers we don't use for sudo*.h files.

Previously we needed to include headers required by the various
sudo*h files.  Now those files are more self-sufficient and we
should only include headers needed by code in the various .c files.

lib/util/secure_path.c

@@ -23,17 +23,13 @@
 
 #include <config.h>
 
-#include <sys/types.h>
 #include <sys/stat.h>
-#include <stdio.h>
 #ifdef HAVE_STRING_H
 # include <string.h>
 #endif /* HAVE_STRING_H */
 #ifdef HAVE_STRINGS_H
 # include <strings.h>
 #endif /* HAVE_STRINGS_H */
-#include <unistd.h>
-#include <errno.h>
 
 #include "sudo_compat.h"
 #include "sudo_util.h"