skip update_inventory during character init

With a debugging pline() in place, I could see that tty perm_invent
was being redrawn for each item added to hero's initial inventory.
Avoid that.  There is an update_inventory() call just prior to
entering moveloop() which handles all of starting invent as a unit.

src/invent.c

@@ -2407,6 +2407,8 @@ update_inventory(void)
 {
     int save_suppress_price;
 
+    if (!g.program_state.in_moveloop) /* not covered by suppress_map_output */
+        return;
     if (suppress_map_output()) /* despite name, used for perm_invent too */
         return;