linux: generic: dsa: mv88e6xx: Drop obsolete patch

As described by Tobias Waldekranz this patch is obsolete
and the issue is already fixed in the upstream kernels we
are using.

Link: http://lists.openwrt.org/pipermail/openwrt-devel/2024-October/043238.html
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

target/linux/generic/pending-6.6/768-net-dsa-mv88e6xxx-Request-assisted-learning-on-CPU-port.patch

@@ -1,27 +0,0 @@
-From:   Tobias Waldekranz <tobias@waldekranz.com>
-Subject: [RFC net-next 7/7] net: dsa: mv88e6xxx: Request assisted learning on CPU port
-Date:   Sat, 16 Jan 2021 02:25:15 +0100
-Archived-At: <https://lore.kernel.org/netdev/20210116012515.3152-8-tobias@waldekranz.com/>
-
-While the hardware is capable of performing learning on the CPU port,
-it requires alot of additions to the bridge's forwarding path in order
-to handle multi-destination traffic correctly.
-
-Until that is in place, opt for the next best thing and let DSA sync
-the relevant addresses down to the hardware FDB.
-
-Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
----
- drivers/net/dsa/mv88e6xxx/chip.c | 1 +
- 1 file changed, 1 insertion(+)
-
---- a/drivers/net/dsa/mv88e6xxx/chip.c
-+++ b/drivers/net/dsa/mv88e6xxx/chip.c
-@@ -7027,6 +7027,7 @@ static int mv88e6xxx_register_switch(str
- 	ds->ops = &mv88e6xxx_switch_ops;
- 	ds->ageing_time_min = chip->info->age_time_coeff;
- 	ds->ageing_time_max = chip->info->age_time_coeff * U8_MAX;
-+	ds->assisted_learning_on_cpu_port = true;
- 
- 	/* Some chips support up to 32, but that requires enabling the
- 	 * 5-bit port mode, which we do not support. 640k^W16 ought to