Add GetKeyboardState to user32

core/sys/windows/user32.odin

@@ -123,6 +123,8 @@ foreign user32 {
 
 	GetKeyState :: proc(nVirtKey: c_int) -> SHORT ---
 	GetAsyncKeyState :: proc(vKey: c_int) -> SHORT ---
+	
+	GetKeyboardState :: proc(lpKeyState: PBYTE) -> BOOL ---
 
 	MapVirtualKeyW :: proc(uCode: UINT, uMapType: UINT) -> UINT ---