Feedback when boomerang hits sink

doc/fixes35.0

@@ -889,6 +889,7 @@ show t-shirt text at end of game inventory disclose
 hitting with a polearm remembers the position of the last monster you hit
 allow showing legal polearm positions when asked for location to hit
 add messages for trying to pick up some terrain features
+boomerang makes noise when hitting a sink
 
 
 Platform- and/or Interface-Specific Fixes

src/zap.c

@@ -3283,8 +3283,10 @@ int dx, dy;
 		}
 		tmp_at(bhitpos.x, bhitpos.y);
 		delay_output();
-		if(IS_SINK(levl[bhitpos.x][bhitpos.y].typ))
+		if(IS_SINK(levl[bhitpos.x][bhitpos.y].typ)) {
+			if (!Deaf) pline("Klonk!");
 			break;	/* boomerang falls on sink */
+		}
 		/* ct==0, initial position, we want next delta to be same;
 		   ct==5, opposite position, repeat delta undoes first one */
 		if (ct % 5 != 0) i += (counterclockwise ? -1 : 1);