net: stmmac: qcom-ethqos: add support for 2.5G BASEX mode

Add support for 2.5G speed in 2500BASEX mode to the QCom ethqos driver.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20240703181500.28491-2-brgl@bgdev.pl


Signed-off-by: Jakub Kicinski <kuba@kernel.org>