more set_int fixes

fake_fire/init.lua

@@ -16,8 +16,8 @@ local function start_smoke(pos, node, clicker, chimney)
 			end, s_handle)
 		end
 		minetest.delete_particlespawner(id)
-		this_spawner_meta:set_int("smoky", nil)
-		this_spawner_meta:set_int("sound", nil)
+		this_spawner_meta:set_int("smoky", 0)
+		this_spawner_meta:set_int("sound", 0)
 		return
 	end
 
@@ -34,7 +34,7 @@ local function start_smoke(pos, node, clicker, chimney)
 		})
 		if chimney == 1 then
 			this_spawner_meta:set_int("smoky", id)
-			this_spawner_meta:set_int("sound", nil)
+			this_spawner_meta:set_int("sound", 0)
 		else
 			s_handle = minetest.sound_play("fire_small", {
 				pos = pos,
@@ -62,8 +62,8 @@ local function stop_smoke(pos)
 		end, s_handle)
 	end
 
-	this_spawner_meta:set_int("smoky", nil)
-	this_spawner_meta:set_int("sound", nil)
+	this_spawner_meta:set_int("smoky", 0)
+	this_spawner_meta:set_int("sound", 0)
 end
 
 minetest.register_node("fake_fire:ice_fire", {