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/pico-imx6ul.h b/include/configs/pico-imx6ul.h
index 1cb8fa6..64e0a55 100644
--- a/include/configs/pico-imx6ul.h
+++ b/include/configs/pico-imx6ul.h
@@ -17,7 +17,7 @@
 
 #define CFG_FEC_MXC_PHYADDR		0x1
 
-#define CONFIG_MXC_UART_BASE		UART6_BASE_ADDR
+#define CFG_MXC_UART_BASE		UART6_BASE_ADDR
 
 /* MMC Configs */
 #define CFG_SYS_FSL_ESDHC_ADDR	USDHC1_BASE_ADDR