drivers: ethernet: stm32: add get_phy() support

[ramram885]

implementation of get_phy() added.

[github-actions]

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[maass-hamburg]

Suggested change

	static const struct device *eth_stm32_hal_get_phy(const struct device *dev)
	{
	ARG_UNUSED(dev);
	return eth_stm32_phy_dev;
	}
	#if DT_HAS_COMPAT_STATUS_OKAY(st_stm32_mdio)
	static const struct device *eth_stm32_hal_get_phy(const struct device *dev)
	{
	ARG_UNUSED(dev);
	return eth_stm32_phy_dev;
	}
	#endif /* DT_HAS_COMPAT_STATUS_OKAY(st_stm32_mdio) */

[maass-hamburg]

Suggested change

	.get_phy = eth_stm32_hal_get_phy,
	#if DT_HAS_COMPAT_STATUS_OKAY(st_stm32_mdio)
	.get_phy = eth_stm32_hal_get_phy,
	#endif

[maass-hamburg]

this PR was first: #80258