add: ksize and vsize

src/kernel.c

@@ -33,6 +33,7 @@ void kernel_main(void)
 	kprintf(KERN_NOTICE "KERN_NOTICE\n");
 	kprintf(KERN_INFO "KERN_INFO\n");
 	kprintf(KERN_DEBUG "KERN_DEBUG\n");
-	vmalloc(10);
+	void *ptr = vmalloc(100);
+	kprintf("%d\n", ksize(ptr));
 	shell_init();
 }