fix #H4404 - Orc wizard vs ring of poison resist

Orcs are innately poison resistant, so orcish wizard's random ring
shouldn't be poison resistance.  Presumeably an orc who is bright
enough to become a wizard is not so dumb as to bring a useless ring
with him/her into the dungeon....

src/u_init.c

@@ -1013,6 +1013,8 @@ register struct trobj *trop;
                    || otyp == RIN_AGGRAVATE_MONSTER
                    || otyp == RIN_HUNGER
                    || otyp == WAN_NOTHING
+                   /* orcs start with poison resistance */
+                   || (otyp == RIN_POISON_RESISTANCE && Race_if(PM_ORC))
                    /* Monks don't use weapons */
                    || (otyp == SCR_ENCHANT_WEAPON && Role_if(PM_MONK))
                    /* wizard patch -- they already have one */