Fixed Elemental Change skills versus players (fixes #1411)

* Should not be usable on players or Status Immune monsters.

src/map/skill.c

@@ -7888,7 +7888,7 @@ int skill_castend_nodamage_id (struct block_list *src, struct block_list *bl, ui
 	case SA_ELEMENTFIRE:
 	case SA_ELEMENTGROUND:
 	case SA_ELEMENTWIND:
-		if (sd && !dstmd && status_has_mode(tstatus,MD_STATUS_IMMUNE)) // Only works on non-immune monsters.
+		if (sd && (!dstmd || status_has_mode(tstatus,MD_STATUS_IMMUNE))) // Only works on monsters (Except status immune monsters).
 			break;
 	case NPC_ATTRICHANGE:
 	case NPC_CHANGEWATER: