Kernel: Add Semaphore to block threads

kernel/include/kernel/Input/PS2Keyboard.h

@@ -4,6 +4,7 @@
 #include <kernel/Input/KeyEvent.h>
 #include <kernel/Input/PS2Controller.h>
 #include <kernel/Input/PS2Keymap.h>
+#include <kernel/Semaphore.h>
 
 namespace Kernel::Input
 {
@@ -60,6 +61,8 @@ namespace Kernel::Input
 
 		State m_state { State::Normal };
 
+		Semaphore m_semaphore;
+
 		BAN::String m_name;
 
 	public: