Merge branch 'net-stmmac-l3-l4-filter-bug-fixes'

Merge branch 'net-stmmac-l3-l4-filter-bug-fixes'

Nazim Amirul says:

====================
net: stmmac: L3/L4 filter bug fixes

This series fixes three bugs in the stmmac L3/L4 TC flower filter
implementation for the XGMAC2 core. All three patches target net.

The L3/L4 filter match count statistics patch (originally patch 4/4)
has been split out and will be sent separately against net-next per
Andrew Lunn's review of v1.

Patch 1 fixes a register corruption bug in the L4 filter port configuration.
The XGMAC_L4_ADDR register holds both source and destination port match
values in a single register. The original code overwrites the entire register
when setting either field, silently erasing the other. This is fixed by
using a read-modify-write sequence.

Patch 2 fixes the basic flow match parser to properly reject unsupported
offload requests with -EOPNOTSUPP instead of silently accepting them.
Unsupported cases include partial protocol masks, non-IPv4 network proto,
and non-TCP/UDP transport proto. Extack messages are now included so users
know exactly which part of the match is unsupported. The -EOPNOTSUPP is
also now returned directly instead of using break, which was silently
discarding the error on FLOW_CLS_REPLACE operations.

Patch 3 fixes a stale action bug on filter deletion. When a filter entry
with a drop action is deleted, the action field was not reset, causing
it to persist and potentially affect subsequent filter configurations.

All three patches fix the original L3/L4 filter implementation introduced in
425eabddaf0f ("net: stmmac: Implement L3/L4 Filters using TC Flower").
====================

Link: https://patch.msgid.link/20260714023716.29865-1-muhammad.nazim.amirul.nazle.asmade@altera.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>