drs: hook down movement, adjust touch hooks (#898)

When Down Motion button is bound, install hooks into the game that
detects down movement via patches.

When Disable Touch option is enabled, don't install touch hooks.

src/spice2x/games/drs/io.h

@@ -20,7 +20,8 @@ namespace games::drs {
             P2_Up,
             P2_Down,
             P2_Left,
-            P2_Right
+            P2_Right,
+            DownMotion
         };
     }