ihk_os_getrusage(): Compile LWK-specific results in mcctrl

1. User asks mcctrl for the result via ihk_os_getrusage() with passing void *
2. mcctrl compiles the results and passes them to the user
3. User interprets it by using the type defined in the LWK-specific header

kernel/fileobj.c

@@ -26,7 +26,7 @@
 #include <pager.h>
 #include <string.h>
 #include <syscall.h>
-#include <rusage.h>
+#include <rusage_private.h>
 
 //#define DEBUG_PRINT_FILEOBJ