Audit rloc()

Most of the time, rloc() is used for teleporting monsters and it's not a
big deal if they can't find somewhere to go. In a few cases, it is. I
went through all the callsites and made calls to rloc() not cause
impossible()s if they don't need to.

Fixes a bug/suite of bugs reported by ais523.

src/dothrow.c

@@ -1655,7 +1655,7 @@ nopick:
     if (!Blind)
         pline1(buf);
     if (!tele_restrict(mon))
-        (void) rloc(mon, FALSE);
+        (void) rloc(mon, TRUE);
     return (ret);
 }