Fix infravision monsters flickering when manipulating inventory (#6687)

Source/items.cpp

@@ -2791,8 +2791,6 @@ void CalcPlrItemVals(Player &player, bool loadgfx)
 	player._pILMinDam = lmin;
 	player._pILMaxDam = lmax;
 
-	player._pInfraFlag = false;
-
 	player._pBlockFlag = false;
 	if (player._pClass == HeroClass::Monk) {
 		if (player.InvBody[INVLOC_HAND_LEFT]._itype == ItemType::Staff && player.InvBody[INVLOC_HAND_LEFT]._iStatFlag) {

Source/player.cpp

@@ -1466,6 +1466,7 @@ void ValidatePlayer()
 	}
 
 	myPlayer._pMemSpells &= msk;
+	myPlayer._pInfraFlag = false;
 }
 
 void CheckCheatStats(Player &player)