Ensure the update's production report isn't split by bulletins

During the update, wu() sends TEL_UPDATE telegrams ("Production
Report") instead of TEL_BULLETIN telegrams, but typed_wu() has no such
logic.  It's used by tele(), which doesn't run during the update, and
mpr(), which may, e.g. called from ship or mission code used by
autonav or sail.  This inserts bulletins in the middle of the
production report, splitting it apart.

Happens since mpr() was added in Empire 2.  Before, only tele() used
typed_wu() directly, and everything else wu().

Change mpr() to use wu().

src/lib/subs/pr.c

@@ -482,7 +482,7 @@ mpr(int cn, char *format, ...)
     (void)vsprintf(buf, format, ap);
     va_end(ap);
     if (update_running || cn != player->cnum)
-	typed_wu(0, cn, buf, TEL_BULLETIN);
+	wu(0, cn, "%s", buf);
     else
 	pr_player(player, C_DATA, buf);
 }