Kernel: PIT now has very barebones sleep

kernel/include/kernel/PIT.h

@@ -8,7 +8,7 @@ namespace PIT
 {
 
 	uint64_t ms_since_boot();
-
 	void initialize();
+	void sleep(uint64_t);
 
 }

kernel/kernel/PIT.cpp

@@ -50,4 +50,11 @@ namespace PIT
 		InterruptController::get().enable_irq(PIT_IRQ);
 	}
 
+	void sleep(uint64_t ms)
+	{
+		uint64_t end = s_system_time + ms;
+		while (s_system_time < end)
+			asm volatile("hlt");
+	}
+
 }