mmc: sd: Define name for default speed dtr

Add a new define for the sd default speed 25MHz case
Signed-off-by: Yinbo Zhu <yinbo.zhu@nxp.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

include/linux/mmc/card.h

@@ -156,6 +156,7 @@ struct sd_switch_caps {
 #define UHS_DDR50_MAX_DTR	50000000
 #define UHS_SDR25_MAX_DTR	UHS_DDR50_MAX_DTR
 #define UHS_SDR12_MAX_DTR	25000000
+#define DEFAULT_SPEED_MAX_DTR	UHS_SDR12_MAX_DTR
 	unsigned int		sd3_bus_mode;
 #define UHS_SDR12_BUS_SPEED	0
 #define HIGH_SPEED_BUS_SPEED	1