mx23evk: Fix DDR pin iomux settings

Change MUX_CONFIG_EMI to use the same drive strength as the bootlets code from
Freescale, which results in much better stability.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/board/freescale/mx23evk/spl_boot.c b/board/freescale/mx23evk/spl_boot.c
index b6f4e7e..8da992b 100644
--- a/board/freescale/mx23evk/spl_boot.c
+++ b/board/freescale/mx23evk/spl_boot.c
@@ -26,7 +26,7 @@
 #include <asm/arch/sys_proto.h>
 
 #define	MUX_CONFIG_SSP1	(MXS_PAD_3V3 | MXS_PAD_8MA | MXS_PAD_PULLUP)
-#define	MUX_CONFIG_EMI	(MXS_PAD_3V3 | MXS_PAD_16MA | MXS_PAD_PULLUP)
+#define	MUX_CONFIG_EMI	(MXS_PAD_3V3 | MXS_PAD_12MA | MXS_PAD_PULLUP)
 
 const iomux_cfg_t iomux_setup[] = {
 	/* DUART */