global: Migrate CONFIG_MXC_UART_BASE to CFG

Perform a simple rename of CONFIG_MXC_UART_BASE to CFG_MXC_UART_BASE

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/include/configs/imx6ulz_smm_m2.h b/include/configs/imx6ulz_smm_m2.h
index c95038e..9da98d0 100644
--- a/include/configs/imx6ulz_smm_m2.h
+++ b/include/configs/imx6ulz_smm_m2.h
@@ -12,7 +12,7 @@
 #include <linux/sizes.h>
 #include <linux/stringify.h>
 
-#define CONFIG_MXC_UART_BASE		UART4_BASE
+#define CFG_MXC_UART_BASE		UART4_BASE
 
 #ifndef CONFIG_SPL_BUILD