board: trats2: fix environmental variables

In this patch variable names are used instead of hardcoded names

Signed-off-by: Piotr Wilczek <p.wilczek@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

include/configs/trats2.h

@@ -199,11 +199,11 @@
 	"rootfstype=ext4\0" \
 	"console=" CONFIG_DEFAULT_CONSOLE \
 	"kernelname=uImage\0" \
-	"loaduimage=ext4load mmc ${mmcdev}:${mmcbootpart} 0x40007FC0 uImage\0" \
-		"0x40007FC0 ${kernelname}\0" \
+	"loaduimage=ext4load mmc ${mmcdev}:${mmcbootpart} 0x40007FC0 " \
+		"${kernelname}\0" \
 	"loaddtb=ext4load mmc ${mmcdev}:${mmcbootpart} ${fdtaddr} " \
 		"${fdtfile}\0" \
-	"mmcdev=0\0" \
+	"mmcdev=CONFIG_MMC_DEFAULT_DEV\0" \
 	"mmcbootpart=2\0" \
 	"mmcrootpart=5\0" \
 	"opts=always_resume=1\0" \