net: stmmac: reset residual action in L3L4 filters on delete

net: stmmac: reset residual action in L3L4 filters on delete

When deleting an L3/L4 flower filter entry, the action field is not
reset. If a filter was previously configured with a drop action, that
action may persist and affect subsequent filter configurations
unintentionally.

Clear the action field when the filter entry is deleted.

Fixes: 425eabddaf0f ("net: stmmac: Implement L3/L4 Filters using TC Flower")
Signed-off-by: Rohan G Thomas <rohan.g.thomas@altera.com>
Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260714023716.29865-5-muhammad.nazim.amirul.nazle.asmade@altera.com
Reviewed-by: Jakub Raczynski <j.raczynski@samsung.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>