hw/net/lan9118_phy: Reuse in imx_fec and consolidate implementations

hw/net/lan9118_phy: Reuse in imx_fec and consolidate implementations

imx_fec models the same PHY as lan9118_phy. The code is almost the same with
imx_fec having more logging and tracing. Merge these improvements into
lan9118_phy and reuse in imx_fec to fix the code duplication.

Some migration state how resides in the new device model which breaks migration
compatibility for the following machines:
* imx25-pdk
* sabrelite
* mcimx7d-sabre
* mcimx6ul-evk

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20241102125724.532843-3-shentey@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>