devkit8000: add rootwait to mmcboot option

Signed-off-by: NAndreas Bießmann <biessmann@corscience.de>
cc: Thomas Weber <weber@corscience.de>

include/configs/devkit8000.h

@@ -198,6 +198,7 @@
 		"run commonargs; " \
 		"setenv bootargs ${bootargs} " \
 		"root=/dev/mmcblk0p2 " \
+		"rootwait " \
 		"${kernelopts}\0" \
 	"nandargs=" \
 		"run commonargs; " \