net: phy: Replace PHY_ANEG_TIMEOUT with Kconfig symbol

Switch PHY_ANEG_TIMEOUT to CONFIG_PHY_ANEG_TIMEOUT Kconfig symbol.
This removes one more configuration headers option finalizes its
Kconfig symbol conversion. No functional change expected.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/configs/imx8mp-icore-mx8mp-edimm2.2_defconfig b/configs/imx8mp-icore-mx8mp-edimm2.2_defconfig
index 3a62272..05f68c7 100644
--- a/configs/imx8mp-icore-mx8mp-edimm2.2_defconfig
+++ b/configs/imx8mp-icore-mx8mp-edimm2.2_defconfig
@@ -87,6 +87,7 @@
 CONFIG_MMC_HS400_ES_SUPPORT=y
 CONFIG_MMC_HS400_SUPPORT=y
 CONFIG_FSL_USDHC=y
+CONFIG_PHY_ANEG_TIMEOUT=20000
 CONFIG_PHY_MICREL=y
 CONFIG_PHY_MICREL_KSZ90X1=y
 CONFIG_DWC_ETH_QOS=y