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

arch/x86/kernel/include/arch/rusage.h

@@ -7,7 +7,7 @@
 #define IHK_OS_PGSIZE_2MB 1
 #define IHK_OS_PGSIZE_1GB 2
 
-extern struct ihk_os_monitor *monitor;
+extern struct rusage_global *rusage;
 
 extern int sprintf(char * buf, const char *fmt, ...);