Fix Stair Variant Drops

Seems to have been broken in https://github.com/GTNewHorizons/Chisel/commit/f0e11d8eeea751a60c0ecf2d3a40643017e11f1b

src/main/java/team/chisel/block/BlockCarvableStairs.java

@@ -40,7 +40,7 @@ public class BlockCarvableStairs extends BlockStairs implements ICarvable {
 
     @Override
     public int damageDropped(int i) {
-        return i / 8;
+        return i & 0x8;
     }
 
     @Override