net: mpc8xx_fec: Migrate to DM_ETH

Migrate mpc8xx_fec driver to DM_ETH.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 93e7dbe..0070ff7 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -744,6 +744,7 @@
 config MPC8XX_FEC
 	bool "Fast Ethernet Controller on MPC8XX"
 	depends on MPC8xx
+	depends on DM_ETH
 	select MII
 	select SYS_DISCOVER_PHY
 	help