rtl93xx: fix condition intended to only select internal serdes ports

rtl93xx: fix condition intended to only select internal serdes ports

This condition was introduced in commit 51c8f7661244 ("realtek: Improve
MAC config handling for all SoCs") to correctly report the speed of the
internal serdes ports as 10G, but instead makes all ports read 10G
because the or-operator should have been an and-operator.

Fixes: #9953
Fixes: 51c8f7661244 ("realtek: Improve MAC config handling for all SoCs")
Signed-off-by: Peter Körner <git@mazdermind.de>
[ wrap comment to 72 column and improve commit ref ]
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>