remove a set_uasmon() call from iter_mons() processing

Reported by hackemslashem.

include/decl.h

@@ -1061,6 +1061,7 @@ struct instance_globals_w {
 
     /* new */
     struct win_settings wsettings;      /* wintype.h */
+    long were_changes;                  /* were.c, allmain.c */
 
     boolean havestate;
     unsigned long magic; /* validate that structure layout is preserved */

src/allmain.c

@@ -201,6 +201,7 @@ moveloop_core(void)
                 struct monst *mtmp;
 
                 /* set up for a new turn */
+                gw.were_changes = 0L;
                 mcalcdistress(); /* adjust monsters' trap, blind, etc */
 
                 /* reallocate movement rations to monsters; don't need
@@ -324,6 +325,11 @@ moveloop_core(void)
                     (void) dosearch0(1);
                 if (Warning)
                     warnreveal();
+                if (gw.were_changes) {
+                    /* update innate intrinsics (mainly Drain_resistance) */
+                    set_uasmon();
+                    gw.were_changes = 0L;
+                }
                 mkot_trap_warn();
                 dosounds();
                 do_storms();

src/decl.c

@@ -863,6 +863,7 @@ static const struct instance_globals_w g_init_w = {
     UNDEFINED_PTR, /* wportal */
     /* new */
     { wdmode_traditional, NO_COLOR },       /* wsettings */
+    0L,                                     /* were.c, allmain.c */
     TRUE, /* havestate*/
     IVMAGIC  /* w_magic to validate that structure layout has been preserved */
 };

src/were.c

@@ -16,6 +16,7 @@ were_change(struct monst *mon)
             && !rn2(night() ? (flags.moonphase == FULL_MOON ? 3 : 30)
                             : (flags.moonphase == FULL_MOON ? 10 : 50))) {
             new_were(mon); /* change into animal form */
+            gw.were_changes++;
             if (!Deaf && !canseemon(mon)) {
                 const char *howler;
 
@@ -39,9 +40,8 @@ were_change(struct monst *mon)
         }
     } else if (!rn2(30) || Protection_from_shape_changers) {
         new_were(mon); /* change back into human form */
+        gw.were_changes++;
     }
-    /* update innate intrinsics (mainly Drain_resistance) */
-    set_uasmon(); /* new_were() doesn't do this */
 }
 
 int
@@ -203,6 +203,7 @@ you_were(void)
             return;
     }
     (void) polymon(u.ulycn);
+    gw.were_changes++;
 }
 
 void