Require a clear head to #offer

This will increase the potential challenge involved in donning a helm of
opposite alignment on Astral, now that it confuses the hero -- it means
that you must spend at least a turn after putting on the helm clearing
the confusion.  Since putting on the helm of opposite alignment may also
summon erinyes, this hopefully turns it from a situation where it's a
no-brainer to immediately ditch them by #offering the Amulet of Yendor
into one where the player must actually stop and think a little bit.

src/pray.c

@@ -1810,6 +1810,9 @@ dosacrifice(void)
     if (!on_altar() || u.uswallow) {
         You("are not standing on an altar.");
         return ECMD_OK;
+    } else if (Confusion || Stunned || Hallucination) {
+        You("are too impaired to perform the rite.");
+        return ECMD_OK;
     }
     highaltar = (levl[u.ux][u.uy].altarmask & AM_SANCTUM);