realtek: rtl93xx: Ignore STP for per port TX

realtek: rtl93xx: Ignore STP for per port TX

If transmissions are done outside of the DSA switch (directly from the CPU
port), the STP state must not block the transmission. Otherwise, STP frames
are not correctly submitted and the STP frames cannot correctly detect
loops before switching a port in the forwarding state.

The same applies for the LLDP frames. These must be submitted independent
of the STP state to identify neighbors or configure POE limits.

It is not necessary to filter specific destination mac addresses because
the transmission was done outside the bridge/switch in the first place. The
transmission is therefore forced.

Signed-off-by: Issam Hamdi <ih@simonwunderlich.de>
Co-developed-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Link: https://github.com/openwrt/openwrt/pull/20184
Signed-off-by: Robert Marko <robimarko@gmail.com>