fix: update frame count when allocating some

src/kernel.c

@@ -27,6 +27,6 @@ void kernel_main(void)
 	init_memory();
 	char *str = (char *)kalloc_frame(1);
 	memcpy(str, "Hello world!\n", 15);
-	kprintf(KERN_INFO, "%s", str);
+	kprintf(KERN_INFO, "%d: %s", str, str);
 	shell_init();
 }