Kernel: Add scancode value to KeyEvent

Author: https://github.com/asliturk
Commit: 46b92fa173
Pull-request: https://github.com/SerenityOS/serenity/pull/2455
Reviewed-by: https://github.com/JonArcherII
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/bugaevc

Kernel/KeyCode.h

@@ -160,6 +160,7 @@ enum KeyModifier {
 
 struct KeyEvent {
     KeyCode key { Key_Invalid };
+    u32 scancode { 0 };
     u8 character { 0 };
     u8 flags { 0 };
     bool alt() const { return flags & Mod_Alt; }