More source headers harmonization

* fix missing #ifdefs
* remove spaces and page feeds
* follow same set of rules everywhere, with cdio includes coming
  after standard C includes.

lib/driver/realpath.c

@@ -40,7 +40,9 @@
 # include <stdlib.h>
 #endif
 
-#include <stdio.h>
+#ifdef HAVE_STDIO_H
+# include <stdio.h>
+#endif
 
 #ifdef HAVE_STRING_H
 # include <string.h>
@@ -50,7 +52,6 @@
 # include <unistd.h>
 #endif
 
-
 #ifdef HAVE_INTTYPES_H
 # include "inttypes.h"
 #endif