Convert CONFIG_MCFUART to Kconfig

This converts the following to Kconfig:
	CONFIG_MCFUART

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/M53017EVB_defconfig b/configs/M53017EVB_defconfig
index d8f78b0..1cd48d6 100644
--- a/configs/M53017EVB_defconfig
+++ b/configs/M53017EVB_defconfig
@@ -34,3 +34,4 @@
 CONFIG_DM_ETH=y
 CONFIG_MCFFEC=y
 CONFIG_MII=y
+CONFIG_MCFUART=y