touchscreen: Don't read if no reading requested

Signed-off-by: Daniel Schaefer <dhs@frame.work>

Author: JohnAZoidberg

framework_lib/src/touchscreen_win.rs

@@ -80,6 +80,10 @@ pub fn send_message(handle: &HANDLE, message_id: u8, read_len: usize, data: Vec<
         );
         debug!("    Success: {}", success);
 
+        if read_len == 0 {
+            return Some(vec![]);
+        }
+
         let mut bytes_read = 0;
         debug!("  ReadFile");
         // HidD_GetFeature doesn't work, have to use ReadFile