net: dwc_eth_qos: use generic ethernet phy for stm32 variant

Use the generic ethernet phy which already manages the correct binding
for gpio reset, including the assert an deassert delays.

Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 726ad36..130db9f 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -206,6 +206,7 @@
 config DWC_ETH_QOS_STM32
 	bool "Synopsys DWC Ethernet QOS device support for STM32"
 	depends on DWC_ETH_QOS
+	select DM_ETH_PHY
 	default y if ARCH_STM32MP
 	help
 	  The Synopsys Designware Ethernet QOS IP block with the specific