drivers: eth: phy: add Motorcomm YT8521 PHY driver Add PHY driver for Motorcomm YT8521 which is used on FRDM_IMX93 board. Signed-off-by: Hongbo Wang <hongbo.wang@nxp.com> Signed-off-by: Jiafei Pan <jiafei.pan@nxp.com> Signed-off-by: Chekhov Ma <chekhov.ma@nxp.com>